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          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany" xlink:label="dei_EntityEmergingGrowthCompany"/>
          <link:loc xlink:type="locator" xlink:href="ftci-20250630.xsd#ftci_AggregateBalanceOfUnrestrictedCash" xlink:label="ftci_AggregateBalanceOfUnrestrictedCash"/>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Proceeds from Sale of Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SoftwareDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Software Development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SoftwareDevelopmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capitalized Software [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseOfPropertyAndEquipmentIncludedInAccountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purchase of property and equipment included in account payable.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseOfPropertyAndEquipmentIncludedInAccountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Of Property And Equipment Included In Account Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseOfPropertyAndEquipmentIncludedInAccountPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchases of property and equipment included in ending accounts payable and accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityIncorporationStateCountryCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Incorporation, State or Country Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Preferred Stock, Shares Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Balance Sheet Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance Sheet Location</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_NetProfitAttributable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Net profit attributable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_NetProfitAttributable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net profit attributable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_NetProfitAttributable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Profit Attributable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCurrentReportingStatus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Current Reporting Status</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyDamagesSoughtValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Damages sought value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LossContingencyDamagesSoughtValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Loss Contingency, Damages Sought, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromWarrantExercises_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Warrant Exercises</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpensesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PaidInKindNonCashInterestAddedToSeniorNotesPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Paid In Kind Non Cash Interest Added To Senior Notes principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PaidInKindNonCashInterestAddedToSeniorNotesPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Paid In Kind Non Cash Interest Added To Senior Notes principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PaidInKindNonCashInterestAddedToSeniorNotesPrincipal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Paid-in-kind non-cash interest added to Senior Notes principal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SharesIssuedForLegalSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Shares issued for legal settlement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SharesIssuedForLegalSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares issued for legal settlement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SharesIssuedForLegalSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued for legal settlement, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductOrServiceAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ImpactOfAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impact of adoption of ASU 2016-13, effective January 1, 2023</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ImpactOfAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impact Of Adoption</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ImpactOfAdoption_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Impact of adoption.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalPeriodFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Document Fiscal Period Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessTable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Business [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description Of Business [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncurrentLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Noncurrent Liabilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncurrentLiabilitiesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Noncurrent Liabilities [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityShellCompany_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Shell Company</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase commitment of contractual obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contractual Obligation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractualObligation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Contractual Obligation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ServiceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Service [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ServiceMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and Cash Equivalents, at Carrying Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and Cash Equivalents, at Carrying Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cash and Cash Equivalents, at Carrying Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfProject_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain on sale of Atlas</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfProject_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Sale of Project</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfProject_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain on sale of Atlas</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsidiary, Sale of Stock [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Shares, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock issued for notes purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDeposits_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Vendor deposits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDeposits_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vendor Deposits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDeposits_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vendor deposits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyDescription_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty description</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OriginalWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Original Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OriginalWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Original Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OriginalWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Original Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Debt, Net of Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromDebtNetOfIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Proceeds Received on Closing Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedForAccruedLegalSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock issued for accrued legal settlement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedForAccruedLegalSettlement_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock issued for accrued legal settlement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFilerCategory_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Filer Category</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Other Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment in Alpha Steel</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquireOtherInvestments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Equity method investment in Alpha Steel</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities and stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payables and Accruals [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PayablesAndAccrualsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty accruals are reported in:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SouthLakeOneLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">South Lake One LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SouthLakeOneLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">South Lake One LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SouthLakeOneLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">South Lake One LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InflationReductionActOfTwoThousandTwentyTwoPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inflation Reduction Act Of Two Thousand TwentyTwo Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InflationReductionActOfTwoThousandTwentyTwoPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Inflation Reduction Act Of Two Thousand TwentyTwo Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InflationReductionActOfTwoThousandTwentyTwoPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inflation Reduction Act of 2022 ("IRA")</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RetireAggregateSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Retire Aggregate Shares of Common Stock.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RetireAggregateSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retire Aggregate Shares of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RetireAggregateSharesOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Retire aggregate shares of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard and Extended Product Warranty Accrual, Decrease for Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Standard and Extended Product Warranty Accrual, Decrease for Payments, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Settlements made during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Remaining Amortization Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortized period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statutory rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AmountsChargedToEarningsDuringThePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amounts Charged to Earnings During the Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AmountsChargedToEarningsDuringThePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amounts Charged to Earnings During the Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AmountsChargedToEarningsDuringThePeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts charged to earnings during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCreditsAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Credits and Other Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCreditsAndOtherLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-federal tax obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Goodwill_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Goodwill, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Noncash Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Noncash Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNoncashIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Lease expense and other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TaihuaNewEnergyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Taihua New Energy [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TaihuaNewEnergyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taihua New Energy [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeStockOptionMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock Options [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Taxes Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxesPaid_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid during the period for taxes, net of refunds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoods_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Finished Goods, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoods_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finished goods</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryFinishedGoods_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Inventory, Finished Goods, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Reconciliation Including Such Costs to Our Consolidated Net Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Inventory, Current [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfInventoryCurrentTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sale of Atlas software platform</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Significant Accounting Policies [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of significant accounting policies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_MajorCustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Major Customers [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_MajorCustomersMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Major Customers [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Asset, Useful Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetUsefulLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, estimated useful life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalInterestRateAbovePrime_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional Interest Rate Above Prime</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalInterestRateAbovePrime_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Interest Rate Above Prime</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalInterestRateAbovePrime_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Interest Rate Above Prime</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Computation of Basic and Diluted Income (Loss) Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets and Liabilities, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Other Operating Assets and Liabilities, Net, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Lease payments and other, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Senior Notes, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Senior notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WorkforceActivityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Workforce Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WorkforceActivityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Workforce Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Basic loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Accrual</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end 's period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Balance at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockCapitalSharesReservedForFutureIssuanceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common Stock, Capital Shares Reserved for Future Issuance Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockCapitalSharesReservedForFutureIssuanceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Capital Shares Reserved for Future Issuance Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockCapitalSharesReservedForFutureIssuanceValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, reserved for future issuance, value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Foreign currency translation adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevolvingCreditFacilityMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_HxTrackerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">HX Tracker [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_HxTrackerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">HX Tracker</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_HxTrackerMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">HX Tracker Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accounts receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments to reconcile net loss to cash used in operating activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2029</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MalpracticeLossContingencyLettersOfCreditAndSuretyBonds_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding surety and performance bonds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MalpracticeLossContingencyLettersOfCreditAndSuretyBonds_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Malpractice Loss Contingency, Letters of Credit and Surety Bonds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntitySmallBusiness_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Small Business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings (Accumulated Deficit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Retained Earnings (Accumulated Deficit), Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Retained Earnings (Accumulated Deficit), Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Retained Earnings (Accumulated Deficit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsRecoverableFromManufacturer_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants recoverable from manufacturer.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsRecoverableFromManufacturer_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Recoverable From Manufacturer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsRecoverableFromManufacturer_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty recoverable from manufacturer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsRecoverableFromManufacturer_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Warranty recoverable from manufacturer</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance Initial Public Offering</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from IPO</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceInitialPublicOffering_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds of IPO</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualExcludingShareBasedPaymentsAndPostretirementBenefitsByTitleOfIndividualAndByTypeOfDeferredCompensationTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Deferred Compensation Arrangement with Individual, Excluding Share-Based Payments and Postretirement Benefits, by Title of Individual and by Type of Deferred Compensation [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ShortTermNonInterestBearingCustomerAdvance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Short term non-interest-bearing customer advance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ShortTermNonInterestBearingCustomerAdvance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short Term Non-Interest-Bearing Customer Advance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ShortTermNonInterestBearingCustomerAdvance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short term non-Interest-Bearing customer advance.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SuretyCollateral_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Surety collateral</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SuretyCollateral_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Surety collateral.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SuretyCollateral_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Surety Collateral</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeasesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leases [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryValuationReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Valuation Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryValuationReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Inventory Valuation Reserves, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryValuationReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Inventory Valuation Reserves, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryValuationReserves_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allowance for slow-moving and obsolete inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryValuationReserves_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Allowance for slow-moving and obsolete inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Lease, Description [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_AmendmentFlag_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amendment Flag</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreasedInDefaultInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increased In Default Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreasedInDefaultInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increased In Default Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreasedInDefaultInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increased in default interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product and Service [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ProductsAndServicesDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product and Service</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Secured promissory notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndFinancingReceivableAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts and Financing Receivable, Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndFinancingReceivableAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndFinancingReceivableAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndFinancingReceivableAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Allowance for credit losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndFinancingReceivableAllowanceForCreditLoss_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Allowance for credit losses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities and Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">LIABILITIES AND STOCKHOLDERS' EQUITY</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressPostalZipCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Postal Zip Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TradeAndOtherAccountsReceivablePolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Net cash used in operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualClassifiedCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Accrual, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualClassifiedCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualClassifiedCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2027</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Interest Rate, Effective Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective interest rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantiesDisclosuresAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranties Disclosures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss per share:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Note 11. Net loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ShortTermInterestBearingLoanCustomerDvance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Short-term Interest Bearing Loan &amp; Customer dvance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ShortTermInterestBearingLoanCustomerDvance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-term Interest Bearing Loan &amp; Customer dvance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Cash Flow Information [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosures of cash flow information:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RelatedPartyAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Related party accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RelatedPartyAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related party accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RelatedPartyAccruals_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related party accrued cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net and goodwill</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDepositsWithRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Vendor Deposits With Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDepositsWithRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Vendor Deposits With Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_VendorDepositsWithRelatedParty_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Vendor deposits with related party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BalanceSheetLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Balance Sheet Location [Axis]</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SignificantChangesInOperationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: significant segment period costs:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease right-of-use assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TranslationAndOther_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Translation and other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TranslationAndOther_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Translation and other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TranslationAndOther_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Translation and other</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentType_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Type</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureIssuanceOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Future Issuance of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureIssuanceOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential Future Issuance of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureIssuanceOfDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential future issuance of debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SettlementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Settlement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SettlementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Settlement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SettlementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Settlement Member</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gross Profit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GrossProfit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gross loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TypeOfArrangementAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement and Arrangement Other than Collaborative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Revenue [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfRevenueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of revenue:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Collaborative Arrangement and Arrangement Other than Collaborative [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Collaborative Arrangement and Arrangement Other than Collaborative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCentralIndexKey_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Central Index Key</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrimeRateMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prime Rate [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assessment Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assessment Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Decrease in cash, cash equivalents and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value Adjustment of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain from change in fair value of warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Less: decrease in fair value of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Less: decrease in fair value of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain (loss) from change in fair value of warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Income, Operating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Income, Operating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestIncomeOperating_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest income</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential common shares excluded from diluted net loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AtmProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ATM Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AtmProgramMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ATM Program [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased and Retired During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share repurchase and retirement (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Share repurchased and retired (Shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchase and retirement of common stock (shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Money Market Funds, at Carrying Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_MoneyMarketFundsAtCarryingValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Carrying value of money market fund</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SunEdisonUtilityHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">SunEdison Utility Holdings Inc. member.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SunEdisonUtilityHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sun Edison Utility Holdings Inc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SunEdisonUtilityHoldingsIncMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">SunEdison Utility Holdings, Inc. [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CbpAssessmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">CBP Assessments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CbpAssessmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">CBP Assessments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CbpAssessmentsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">CBP Assessments [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AynaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Ayna</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AynaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ayna [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AynaMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ayna [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon exercise of stock options, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Asset purchase agreement.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Purchase Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssetPurchaseAgreementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Purchase Agreement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProvisionForInventoryObsolescence_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Expense charge to establish an inventory obsolesce reserve.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProvisionForInventoryObsolescence_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Provision For Inventory Obsolescence</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProvisionForInventoryObsolescence_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Provision for obsolete and slow-moving inventory</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlcBarclaysBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">PLC Barclays Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlcBarclaysBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">PLC Barclays Bank [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlcBarclaysBankMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Barclays Bank PLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capital Contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total accrued expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Restricted Stock Award, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued during the period for vested restricted stock awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Sales [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfSalesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of revenue [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Fiscal Year End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ClassOfWarrantOrRightAggregatePercentageOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Aggregate Percentage of common Stock Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ClassOfWarrantOrRightAggregatePercentageOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Class of Warrant or Right, Aggregate Percentage of common Stock Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ClassOfWarrantOrRightAggregatePercentageOfCommonStockOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate Percentage of common Stock Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of Tariffs classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of Tariffs Classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of tariffs classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Product Warranty Liability [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Changes in Product Warranty Reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Schedule of warranty accruals</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Potential Future Capital Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Potential Future Capital Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PotentialFutureCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Potential future capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentQuarterlyReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Quarterly Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressStateOrProvince_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, State or Province</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentInitialBorrowingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Initial Borrowing Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentInitialBorrowingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument Initial Borrowing Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentInitialBorrowingAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial Term Loans Funded on Closing Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assessment Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assessment Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EquityMethodInvesteeNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_EquityMethodInvesteeNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment, Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Equity Method Investments, Net of Dividends or Distributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss from unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income (Loss) from Equity Method Investments, Net of Dividends or Distributions, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Loss from unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InternalCreditAssessmentAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Internal Credit Assessment [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProductWarrantyLife_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Product warranty life.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProductWarrantyLife_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProductWarrantyLife_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product warranty life</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Sale of Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromSaleOfEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from disposal of investment in unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Stock compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtDiscountAndDeferredDebtCostsBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Discount And Deferred Debt Costs Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtDiscountAndDeferredDebtCostsBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Discount And Deferred Debt Costs Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtDiscountAndDeferredDebtCostsBalance_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: discount and deferred loan costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Issuance of common stock upon exercise of stock options</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedCostOfRevenues_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued cost of revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedCostOfRevenues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued cost of revenues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedCostOfRevenues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OtherAccruedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OtherAccruedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Accrued Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OtherAccruedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Other Accrued Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive income (loss):</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent Event</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Assets, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentInterestRatePaidInKind_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Interest Rate, Paid in Kind</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentInterestRatePaidInKind_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Term Debt, paid in kind interest, Percentage Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TamaraMullingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tamara Mullings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TamaraMullingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tamara Mullings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TamaraMullingsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tamara Mullings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">AOCI Attributable to Parent [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Other Comprehensive Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_NameOfMajorCustomerDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Common, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockCommonShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury Stock, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Impairment Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillImpairmentLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment of goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Preferred Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Preferred Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Preferred Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock par value of $0.0001 per share, 10,000,000 shares authorized; none issued as of June 30, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Maturity Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Fair Value of Amount Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MinimumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Intangible Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfIntangibleAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Capital Contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContributions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased and Retired During Period, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Share repurchase and retirement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchase and retirement of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseObligationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Purchase Obligation Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseObligationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Purchase Obligation Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PurchaseObligationPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase Obligation Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net of allowance for credit losses of $1,909 and $1,717 at june 30 ,2025 and December 31, 2024, respectively</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (Note 13)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranties issued and remediation added</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Credit Loss Expense (Reversal)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts charged to earnings during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Credit loss (credits) provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indefinite-Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Present value of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Present value of operating lease liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity, Reverse Stock Split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityReverseStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reverse stock split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Goodwill [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfGoodwillTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of goodwill activity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Additional capital contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional capital contribution</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AdditionalCapitalContribution_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional capital contributions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCashCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyLiabilityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Liability [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyLiabilityLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Warranty Liability [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AmendmentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amendment Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AmendmentWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Amendment Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TradeAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Trade Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TradeAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trade Accounts Receivable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TradeAccountsReceivable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trade receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-federal tax obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted Average Number of Shares Outstanding, Basic, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average shares outstanding for calculating basic and diluted loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfOperatingLeasedAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Operating Leased Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Lived Tangible Asset [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Accrual, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty reserves</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Other non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Credit loss provision</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit loss (credits) provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Credit loss (credits) provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subsequent events</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Long-Term Debt, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transactions Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related party transactions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Cash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">APIC, Share-Based Payment Arrangement, Increase for Cost Recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity, Attributable to Parent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Ending balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Beginning balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total stockholders' equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WorkingCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Working Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WorkingCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Working Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WorkingCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Working capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Par or Stated Value Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, par value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RightOfUseAssetAndLeaseLiabilityRecognitionForNewLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Right-Of-Use Asset And Lease Liability Recognition For New Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RightOfUseAssetAndLeaseLiabilityRecognitionForNewLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Right-Of-Use Asset And Lease Liability Recognition For New Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RightOfUseAssetAndLeaseLiabilityRecognitionForNewLeases_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Right-of-use asset and lease liability recognition for new leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basis of presentation and principles of consolidation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Condensed Consolidated Statement of Stockholders' Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity method investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FcxSolarLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fcx Solar Llc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FcxSolarLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fcx Solar Llc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FcxSolarLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fcx Solar Llc [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UseOfEstimates_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Use of estimates</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InternalCreditAssessmentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Internal Credit Assessment [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Leasehold Improvements [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling and Marketing Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling and marketing [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressAddressLine2_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, Address Line Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralPartnersOfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General Partners' Offering Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralPartnersOfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Agreement offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Equity Method Investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromEquityMethodInvestments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss from unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Operating Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Other Operating Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Interest Expense, Operating and Nonoperating</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Interest Expense, Operating and Nonoperating, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InterestExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOwnershipPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Ownership Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentOwnershipPercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Ownership percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfCondensedFinancialStatementsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Condensed Financial Statements [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_ScheduleOfCondensedFinancialStatementsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revision of previously issued financial statements</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Product and Service Sold</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Cost of Goods and Services Sold, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CostOfGoodsAndServicesSold_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Cost of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Reclassifications_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Reclassifications [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Reclassifications_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reclassifications</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Description and Basis of Presentation [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessDescriptionAndBasisOfPresentationTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of business</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock, Value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Treasury Stock, Value, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Treasury Stock, Value, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Treasury Stock, Value, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Treasury stock, value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury stock, at cost; 1,076,257 shares as of March 31, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TreasuryStockValue_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Treasury stock, at cost; 1,076,257 shares as of June 30, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualPreexistingIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualPreexistingIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in liability for pre-existing warranties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreaseDecreaseInFairValueOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease in Fair Value of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreaseDecreaseInFairValueOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: decrease in fair value of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IncreaseDecreaseInFairValueOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Increase Decrease in Fair Value of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfSeveranceAndTerminationRelatedCostsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of Severance and Termination Related Costs [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfSeveranceAndTerminationRelatedCostsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Severance and Termination Related Costs [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfSeveranceAndTerminationRelatedCostsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of severance and termination-related costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityAddressCityOrTown_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Address, City or Town</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Repurchased During Period, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Repurchase of treasury stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Repurchase of treasury stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_SecurityExchangeName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Security Exchange Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Credit Facility [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CreditFacilityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProgramRightsObligationsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Program Rights Obligations [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfRevisedTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of Revised Tariffs classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfRevisedTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description of Revised Tariffs Classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfRevisedTariffsClassification_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description of revised tariffs classification</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CostOfAssessment_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cost of Assessment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CostOfAssessment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cost of Assessment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CostOfAssessment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cost of assessment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Gross, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Gross, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property, Plant and Equipment, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liability for Unpaid Claims and Claims Adjustment Expense, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Liability for Unpaid Claims and Claims Adjustment Expense, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Liability for Unpaid Claims and Claims Adjustment Expense, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability For Unpaid Claims And Claims Adjustment Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OutstandingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Outstanding Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_OutstandingWarrantsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Outstanding Warrants [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_CounterpartyNameAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pre-tax income (loss) from company's operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Loss before income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EquityMethodInvestmentsFinancialInformationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Equity method investments financial information.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EquityMethodInvestmentsFinancialInformationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments Financial Information [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EquityMethodInvestmentsFinancialInformationTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Equity Method Investments Financial Information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stockholders' Equity Note [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total cash and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total cash, cash equivalents and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise Price of Warrants or Rights</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Total stock compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentPeriodEndDate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Period End Date</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsAndJointVenturesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlacingPurchaseOrders_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Placing purchase orders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlacingPurchaseOrders_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Placing purchase orders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PlacingPurchaseOrders_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Placing Purchase Orders</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of Individual [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Line of Credit Facility, Commitment Fee Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LineOfCreditFacilityCommitmentFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitment fees rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesOfLesseeDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Disclosure [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeasesOfLesseeDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Supplemental Information, Operating Lease</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableNetAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, after Allowance for Credit Loss [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Gain (Loss) on Disposition of Property Plant Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Gain (Loss) on Disposition of Property Plant Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain from sale of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityAvailableRemainingBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revolving Credit Facility, Available Remaining Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityAvailableRemainingBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility, Available Remaining Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityAvailableRemainingBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Available borrowing capacity under the Revolving Credit Facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Financial Position [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfFinancialPositionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Balance sheet</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockUnitsRSUMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted Stock Units (RSU)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses and Other Current Liabilities [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Expenses and Other Current Liabilities Table Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognition</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Reconciliation of cash, cash equivalents and restricted cash at period end:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FernwehEngagedOperatorCompanyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Fernweh Engaged Operator Company LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FernwehEngagedOperatorCompanyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Fernweh Engaged Operator Company LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FernwehEngagedOperatorCompanyLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Fernweh Engaged Operator Company LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DayvLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">DAYV LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DayvLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">DAYV LLC</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DayvLlcMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">DAYV LLC [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SpecialAssessmentBond_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Outstanding surety and performance bonds</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SpecialAssessmentBond_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Special Assessment Bond</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SpecialAssessmentBond_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Special Assessment Bond, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockValueAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Common stock value authorized.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockValueAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Value Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CommonStockValueAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, value authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Prepaid Expenses and Other Current Assets.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expenses and Other Current Assets [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PrepaidExpensesAndOtherCurrentAssetsTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Liabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssumedExerciseOfWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Add: Assumed exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssumedExerciseOfWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assumed Exercise Of Warrant Liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssumedExerciseOfWarrantLiability_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Assumed exercise of warrant liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Deferred Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInDeferredRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity method investments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2026</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SupplementalIncomeStatementElementsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Supplemental Income Statement Elements [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Restricted Cash, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Stock [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">RSUs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RestrictedStockMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Restricted Stock Awards [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_VariableRateAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Variable Rate [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrentAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Finite-Lived Intangible Assets, Gross, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Potential common shares excluded from diluted net loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average shares outstanding for calculating basic and diluted loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Securities Act File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityFileNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity File Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CoverAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cover [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other segment expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherExpenses_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other segment expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Prepaid Expenses and Other Current Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Taxes Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income taxes payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TaxesPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Taxes Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment information</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">General and Administrative Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">General and administrative</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">General and Administrative Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">General and administrative expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_BusinessCombinationAndAssetAcquisitionAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination and Asset Acquisition [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AlphaSteelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Alpha Steel</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AlphaSteelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Alpha Steel [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AlphaSteelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Alpha Steel</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AlphaSteelMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Alpha Steel [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued for HX Tracker acquisition, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares of Common stock purchased</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermDebtTypeDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Finite-Lived Intangible Assets, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Finite-Lived Intangible Assets, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Intangible assets, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investment, Realized Gain (Loss) on Disposal</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gain from disposal of investment in unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Equity Method Investment, Realized Gain (Loss) on Disposal, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentRealizedGainLossOnDisposal_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gain from disposal of investment in unconsolidated subsidiary</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShortTermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Short-Term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Recent accounting and regulatory pronouncements not yet adopted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Future Remaining Lease Payments Obligations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Contract with Customer, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueMinimumCovenantAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Minimum Covenant Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueMinimumCovenantAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue Minimum Covenant Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueMinimumCovenantAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue minimum covenant amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_MinimumBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Minimum Balance Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_MinimumBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Minimum balance covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_MinimumBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum Balance Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Material change in unrecognized tax benefits</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Period Increase (Decrease)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Unrecognized Tax Benefits, Period Increase (Decrease), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Depreciation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantExpirationYears_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrant Expiration Years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantExpirationYears_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrant Expiration Years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantExpirationYears_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warrant expiration years</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Shares, Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Shares, Outstanding, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Shares, Outstanding, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock, shares outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liabilities, current portion (included in Accrued expenses and other current liabilities)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Current portion of operating lease liability</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TechnologyEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Technology Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_TechnologyEquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Information Technology Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentTransitionReport_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Transition Report</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingExpenses_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total operating expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Research and Development Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Investment tax credit, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statement of Cash Flows [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses and Other Current Liabilities Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued Expenses and Other Current Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Expenses and Other Current Liabilities Disclosure Text Block</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ImpactOfStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Impact of stock split.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ImpactOfStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impact of Stock Split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of common stock, value</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net Loss Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PercantageOfConcentrationsOfCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentrations of credit risk, percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PercantageOfConcentrationsOfCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Percantage of Concentrations of credit risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PercantageOfConcentrationsOfCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Percantage of Concentrations of credit risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Inventories, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseCost_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Operating lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxContingencyLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Contingency [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Accounts Receivable Allowance for Credit Loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">ASSETS</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FirstDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">First Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FirstDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">First Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_FirstDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">First Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Increase (Decrease) in Prepaid Expense and Other Assets, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_DocumentFiscalYearFocus_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Document Fiscal Year Focus</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Research and Development Expense [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ResearchAndDevelopmentExpenseMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Research and development [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of prepaid and other current assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Stock Options Exercised</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from stock option exercises</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Value, Acquisitions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodValueAcquisitions_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued for HX Tracker acquisition, Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodSharesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of warrants, Shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodSharesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Shares Exercise Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodSharesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period Shares Exercise Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remainder of 2025</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfIndefiniteLivedIntangibleAssetsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Indefinite-Lived Intangible Assets [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchase cost of shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SaleOfStockConsiderationReceivedOnTransaction_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock, Consideration Received on Transaction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranty</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid, after Year Five</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Thereafter</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Sale of Stock [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EBITDAMinimumCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">E B I T D A Minimum Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EBITDAMinimumCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">E B I T D A Minimum Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_EBITDAMinimumCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">EBITDA minimum covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accrued Expenses and Other Current Liabilities Abstract.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccruedExpensesAndOtherCurrentLiabilitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Expenses and Other Current Liabilities [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProceedsFromDeferredOfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Proceeds from deferred offering costs.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProceedsFromDeferredOfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Deferred Offering Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ProceedsFromDeferredOfferingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred offering costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Method Investments and Joint Ventures Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityMethodInvestmentsDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity method investment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by (used in) investing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Private Placement [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrivatePlacementMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Placement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_Security12bTitle_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Title of 12(b) Security</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfOperatingLeaseAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Schedule of operating lease assets and liabilities.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfOperatingLeaseAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Operating Lease Assets And Liabilities Table [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ScheduleOfOperatingLeaseAssetsAndLiabilitiesTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Supplemental Balance Sheet Information of Leases</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party, Type [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related Party</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredCostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredCostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Cost of Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredCostOfRevenue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AtmProgram_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">ATM Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AtmProgram_lbl" xlink:role="http://www.xbrl.org/2003/role/label">ATM Program</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Liabilities, Noncurrent, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impact on cash from changes in operating assets and liabilities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Description of business.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Description Of Business [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DescriptionOfBusinessLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Description Of Business [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid-in Capital [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional Paid-in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Changes in liability for pre-existing warranties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Senior Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorNotesMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Senior Notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_TradingSymbol_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Trading Symbol</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CashPaidDuringThePeriodForThirdPartyInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Cash paid during the period for third party interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CashPaidDuringThePeriodForThirdPartyInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash paid during the period for third party interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_CashPaidDuringThePeriodForThirdPartyInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash paid during the period for interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TariffsOnMerchandisePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Tariffs on Merchandise, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TariffsOnMerchandisePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tariffs on Merchandise, Percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TariffsOnMerchandisePercent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tariffs on merchandise, percent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_DirectorMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Director [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_DirectorMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Board of Directors</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Event Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementAdjustmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revision of Prior Period, Adjustment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RestatementAdjustmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Adjustments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Finite-Lived Intangible Assets [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of intangible assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityExTransitionPeriod_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Ex Transition Period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtContingentPaymentOfPrincipalOrInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Term Debt, Contingent Payment of Principal or Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtContingentPaymentOfPrincipalOrInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Contingent Payment of Principal or Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Equity Method Investments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Equity Method Investments [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Less imputed interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Selling and Marketing Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Selling and marketing</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SellingAndMarketingExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Selling and Marketing Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ExitFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Exit Fee Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ExitFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Exit Fee Percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ExitFeePercentage_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exit fee percentage</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Components [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Components</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accounts Payable, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsPayableCurrentAndNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total received Invoices from Alpha Steel</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equity Component [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquityComponentDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Equity Component</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ForwardStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Forward stock split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ForwardStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Forward stock split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_ForwardStockSplit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Forward stock split</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard and Extended Product Warranty Accrual</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Standard and Extended Product Warranty Accrual, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_UnrestrictedCashCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrestricted Cash Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_UnrestrictedCashCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Unrestricted Cash Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_UnrestrictedCashCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unrestricted cash covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Percentage Bearing Fixed Interest, Percentage Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-Term Debt, Interest Rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongTermDebtPercentageBearingFixedInterestRate_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Bear interest at the rate</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IPOMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">IPO [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MajorCustomersAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Customer [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Depreciation, Depletion and Amortization, Nonproduction</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Depreciation, Depletion and Amortization, Nonproduction, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DepreciationAndAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Depreciation and amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SecondDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Second Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SecondDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Second Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SecondDelayedDrawTermLoansMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Second Delayed Draw Term Loans [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndOtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts and Other Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndOtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndOtherReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Receivables Collected</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredDebtDiscountAndIssueCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred debt discount and issue costs [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredDebtDiscountAndIssueCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred debt discount and issue costs [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredDebtDiscountAndIssueCostsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred debt discount and issue costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_MaximumMember_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Maximum [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Statistical Measurement [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RangeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statistical Measurement</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Accumulated amortization</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Receivables, Net, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ReceivablesNetCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Expense, Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Prepaid Expense, Current, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amounts charged (credited) to earnings during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Accounts Receivable, Allowance for Credit Loss Expense (Reversal)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss Expense (Reversal)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Credit loss (credits) provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Credit loss (credits) provisions</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentSecondDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Second Delayed Draw Loan Commitment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentSecondDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Debt Instrument Second Delayed Draw Loan Commitment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentSecondDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Second Delayed Draw Term Loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Accounts Payable and Accrued Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accruals and other current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Common Stock, Value, Issued, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock, Value, Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Common Stock, Value, Issued, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Common Stock, Value, Issued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Common stock, value, issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CommonStockValue_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Common stock par value of $0.0001 per share, 850,000,000 shares authorized; 14,872,017 and 12,853,823 shares issued and outstanding as of June 30, 2025 and December 31, 2024</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RecievablesFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Recievables from Related Parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RecievablesFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Recievables from Related Parties</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RecievablesFromRelatedParties_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Related party receivables</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxContingencyTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Contingency [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EquipmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Field Equipment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AggregateOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Aggregate Offering Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AggregateOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Aggregate Offering Price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AggregateOfferingPrice_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate offering price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ImpairmentOrDisposalOfLongLivedAssetsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Impairment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Warrants Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_WarrantsReceived_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Warrants Received</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Amortization of Debt Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Amortization of debt issue costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AmortizationOfFinancingCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Amortization of debt discount and issue costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Preferred Stock, Shares Authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Preferred stock, shares authorized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Debt [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_QuarterEndCashBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Quarter End Cash Balance Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_QuarterEndCashBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Quarter End Cash Balance Covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_QuarterEndCashBalanceCovenant_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Quarter end cash balance covenant</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_NewWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">New Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_NewWarrantMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">New Warrant [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RelatedPartyTransactionLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Related Party Transaction [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue from Contract with Customer [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenueFromContractWithCustomerTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityRegistrantName_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Registrant Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax interest and penalties accrued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtDisclosureTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Disclosure [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAcceleratedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Accelerated Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAcceleratedCompensationCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Increased stock-based compensation expenses</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_LiquidityRatioAmountMinimumLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Liquidity Ratio Amount, Minimum Limit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_LiquidityRatioAmountMinimumLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Liquidity Ratio Amount, Minimum Limit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_LiquidityRatioAmountMinimumLimit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liquidity ratio amount, minimum limit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Nonoperating Income (Expense)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Nonoperating Income (Expense), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other income (expense), net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Additional Paid in Capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Additional Paid in Capital, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Additional Paid in Capital, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Additional Paid in Capital, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subsequent Events [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel">Income tax expense (benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Income tax expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">(Provision for) benefit from income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Provision for income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PersonnelCostsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Personnel Costs Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PersonnelCostsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Personnel Costs Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_PersonnelCostsExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Personnel costs (excluding stock-based compensation)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance of Common Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Proceeds from common stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Common Stock, Shares Outstanding</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Concentration of credit risk</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue, Revenue Recognized</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized included in deferred revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Net Income (Loss) Attributable to Parent, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net Income (Loss) Attributable to Parent, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetIncomeLossAttributableToParentDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss for basic and diluted calculation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated other comprehensive loss</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Accumulated Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Write-offs of accounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Write-offs of accounts</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Receivable, Allowance for Credit Loss, Writeoff</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Payments to Acquire Property, Plant, and Equipment, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property and equipment</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Capital expenditures</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredLongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Secured Long-Term Debt, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredLongTermDebt_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Senior secured term facility</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Assets</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_Assets_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Total assets at period end</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualWarrantiesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Accrual, Increase for Warranties Issued</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualWarrantiesIssued_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Warranties issued and remediation added during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualWarrantiesIssued_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Warranties issued during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Inventory, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InventoryPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Inventories</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IndirectPersonnelCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Indirect Personnel Costs Excluding Stock Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IndirectPersonnelCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Indirect Personnel Costs Excluding Stock Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_IndirectPersonnelCostsExcludingStockBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Indirect personnel costs (excluding stock-based compensation) in cost of revenue</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Statement of operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Restructuring and Related Costs [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument Delayed Draw Loan Commitment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">DebtInstrument Delayed Draw Loan Commitment Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DebtInstrumentDelayedDrawLoanCommitmentAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">First Delayed Draw Term Loans</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndNontradeReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Accounts and Nontrade Receivable [Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AccountsAndNontradeReceivableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts receivable, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Deferred income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Deferred Income Tax Expense (Benefit), Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of shares, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Issuance of common stock (in shares)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Earnings Per Share, Diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Earnings Per Share, Diluted, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Diluted loss per share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Basic and diluted</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">939 Assessment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">939 Assessment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AssessmentMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">939 Assessment [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Title of Individual [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorLongTermNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Senior Notes, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorLongTermNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long term senior secured notes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SeniorLongTermNotes_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Aggregate principal amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AbilityToContinueAsAGoingConcern_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Ability to continue as a going concern</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AbilityToContinueAsAGoingConcern_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Ability to continue as a going concern</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_AbilityToContinueAsAGoingConcern_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liquidity and Going Concern</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/label">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_CityAreaCode_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">City Area Code</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other comprehensive gain (loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Other Comprehensive Income (Loss), Net of Tax, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityGrossMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revolving Credit Facility, Gross Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityGrossMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revolving Credit Facility, Gross Maximum Borrowing Capacity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevolvingCreditFacilityGrossMaximumBorrowingCapacity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Aggregate commitments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentInterestRatePaidInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Investment, Interest Rate, Paid in Cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_InvestmentInterestRatePaidInCash_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Annum paid in cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Debt Instrument, Face Amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt instrument face amount</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Counterparty Name [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="srt_RepurchaseAgreementCounterpartyNameDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Counterparty Name</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyLiabilityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Liability [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProductWarrantyLiabilityTable_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Product Warranty Liability [Table]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period, Shares, Restricted Stock Award, Gross</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Shares issued during the period for vested restricted stock awards, shares</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Shares of common stock issuable upon vesting of restricted stock awards</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Total lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCost_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel">Total lease cost</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LetterOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Letter of Credit [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LetterOfCreditMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Letter of Credit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash and cash equivalents</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Property, Plant and Equipment, Net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Property, Plant and Equipment, Net, Ending Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Property, Plant and Equipment, Net, Beginning Balance</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Property and equipment, net</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Goodwill</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InitialTermLoansFundedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Initial Term Loans Funded [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InitialTermLoansFundedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Initial Term Loans Funded [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_InitialTermLoansFundedMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Initial Term Loans Funded [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Income (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Loss from operations</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill, Foreign Currency Translation, Gain (Loss)</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_GoodwillForeignCurrencyTranslationGainLoss_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Translation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Retained Earnings [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RetainedEarningsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accumulated Deficit</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeBenefitsAndShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Employee Benefits and Share-Based Compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EmployeeBenefitsAndShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Share-based Payment Arrangement, Noncash Expense, Total</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Stock-based compensation expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Deferred Income Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_DeferredIncomeTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Deferred income taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Payments of Stock Issuance Costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock issuance costs</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaymentsOfStockIssuanceCosts_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Stock offering costs paid</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueRecognizedInExcessOfBillings_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue recognized in excess of billings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueRecognizedInExcessOfBillings_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenue recognized in excess of billings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_RevenueRecognizedInExcessOfBillings_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized in excess of billings</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancingInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Financing Interest Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_FinancingInterestExpense_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TermSheetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Term Sheet [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TermSheetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Term Sheet [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TermSheetMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Term Sheet</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Operating lease liability, net of current portion</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by financing activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Asset Acquisition [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_AssetAcquisitionTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of allocation of the purchase price</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Lease, Cost [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LeaseCostTableTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Summary of Lease Expense</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Accrual, Decrease for Payments</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Settlements made during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_StandardProductWarrantyAccrualPayments_lbl" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Settlements made during the period</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Developed Technology Rights [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_DevelopedTechnologyRightsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Developed Technology [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ToolsDiesAndMoldsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Tools, Dies and Molds [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ToolsDiesAndMoldsMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Tooling [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Secured Notes [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_SecuredDebtMember_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Secured Debt [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodValuesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Stock Issued During Period Values Exercise Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodValuesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Stock Issued During Period Values Exercise Of Warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodValuesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Exercise of warrants</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_StockIssuedDuringPeriodValuesExerciseOfWarrants_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Fair value of common stock issued upon warrant exercise</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Income Per Share</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityInteractiveDataCurrent_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Interactive Data Current</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncomeStatementLocationDomain_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Income Statement Location [Domain]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from operating activities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaidInKindInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Paid-in-Kind Interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaidInKindInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Paid-in-kind non-cash interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PaidInKindInterest_lbl" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Paid-in-kind interest</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Increase (Decrease) in Other Noncurrent Liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other non-current liabilities</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SubscriptionRevenueContractTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Subscription revenue contract terms.</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SubscriptionRevenueContractTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Subscription Revenue Contract Terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_SubscriptionRevenueContractTerms_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Subscription revenue contract terms</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_EntityTaxIdentificationNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Entity Tax Identification Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Revenues [Abstract]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_RevenuesAbstract_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue:</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Prepaid Taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_PrepaidTaxes_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Prepaid taxes</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Long-Term Debt, Type [Axis]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes on cash, cash equivalents and restricted cash</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TreasuryStock1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/documentation">Treasury Stock -1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TreasuryStock1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Treasury Stock -1 [Member]</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="ftci_TreasuryStock1Member_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Treasury Stock</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds from Issuance or Sale of Equity</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sale of common stock</link:label>
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          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/label">Local Phone Number</link:label>
          <link:label xml:lang="en-US" xlink:type="resource" xlink:label="dei_LocalPhoneNumber_lbl" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Local Phone Number</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseCost" xlink:label="us-gaap_OperatingLeaseCost"/>
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        <link:calculationLink xlink:type="extended" xlink:role="http://www.ftcsolar.com/20250630/taxonomy/role/DisclosureLeasesSummaryOfFutureRemainingLeasePaymentsObligationsDetails">
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" order="0" weight="1" use="optional"/>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" order="2" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" order="3" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" order="4" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" order="5" weight="1" use="optional"/>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_PropertyPlantAndEquipmentGross" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" order="1" weight="-1" use="optional"/>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="us-gaap_PropertyPlantAndEquipmentGross"/>
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        </link:calculationLink>
        <link:calculationLink xlink:type="extended" xlink:role="http://www.ftcsolar.com/20250630/taxonomy/role/DisclosureIntangibleAssetsNetAndGoodwillSummaryOfIntangibleAssetsDetails">
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsGross" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" order="1" weight="-1" use="optional"/>
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        </link:calculationLink>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="ftci_AccruedCostOfRevenues" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OtherLiabilitiesCurrent" xlink:to="us-gaap_ProductWarrantyAccrualClassifiedCurrent" order="0" weight="1" use="optional"/>
          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="ftci_OtherAccruedCompensation" order="1" weight="1" use="optional"/>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="ftci_RelatedPartyAccruals" order="2" weight="1" use="optional"/>
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          <link:calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent" order="4" weight="1" use="optional"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="us-gaap_AccruedLiabilitiesCurrent"/>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="us-gaap_OtherLiabilitiesCurrent"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualClassifiedCurrent" xlink:label="us-gaap_ProductWarrantyAccrualClassifiedCurrent"/>
          <link:loc xlink:type="locator" xlink:href="ftci-20250630.xsd#ftci_OtherAccruedCompensation" xlink:label="ftci_OtherAccruedCompensation"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent"/>
          <link:loc xlink:type="locator" xlink:href="ftci-20250630.xsd#ftci_RelatedPartyAccruals" xlink:label="ftci_RelatedPartyAccruals"/>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCreditsAndOtherLiabilitiesCurrent" xlink:label="us-gaap_DeferredCreditsAndOtherLiabilitiesCurrent"/>
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    </xsd:appinfo>
  </xsd:annotation>
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  <xsd:element id="ftci_RevolvingCreditFacilityGrossMaximumBorrowingCapacity" name="RevolvingCreditFacilityGrossMaximumBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_PotentialFutureCapitalContributions" name="PotentialFutureCapitalContributions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_OtherAccruedCompensation" name="OtherAccruedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_StockIssuedForAccruedLegalSettlement" name="StockIssuedForAccruedLegalSettlement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_PercantageOfConcentrationsOfCreditRisk" name="PercantageOfConcentrationsOfCreditRisk" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ftci_CommonStockValueAuthorized" name="CommonStockValueAuthorized" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_WorkingCapital" name="WorkingCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_ExitFeePercentage" name="ExitFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_CashPaidDuringThePeriodForThirdPartyInterest" name="CashPaidDuringThePeriodForThirdPartyInterest" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AdditionalCapitalContributions" name="AdditionalCapitalContributions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_TradeAccountsReceivable" name="TradeAccountsReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_RelatedPartyAccruals" name="RelatedPartyAccruals" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_RevolvingCreditFacilityAvailableRemainingBorrowingCapacity" name="RevolvingCreditFacilityAvailableRemainingBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_StockIssuedDuringPeriodValuesExerciseOfWarrants" name="StockIssuedDuringPeriodValuesExerciseOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_FcxSolarLlcMember" name="FcxSolarLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AtmProgram" name="AtmProgram" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_DeferredDebtDiscountAndIssueCostsPolicyTextBlock" name="DeferredDebtDiscountAndIssueCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_ProceedsFromDeferredOfferingCosts" name="ProceedsFromDeferredOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AdditionalCapitalContribution" name="AdditionalCapitalContribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AmountsChargedToEarningsDuringThePeriod" name="AmountsChargedToEarningsDuringThePeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_SuretyCollateral" name="SuretyCollateral" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AtmProgramMember" name="AtmProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AssessmentTypeDomain" name="AssessmentTypeDomain" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AynaMember" name="AynaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_PlacingPurchaseOrders" name="PlacingPurchaseOrders" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_IncreaseDecreaseInFairValueOfWarrants" name="IncreaseDecreaseInFairValueOfWarrants" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_OriginalWarrantsMember" name="OriginalWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_DescriptionOfBusinessTable" name="DescriptionOfBusinessTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_RightOfUseAssetAndLeaseLiabilityRecognitionForNewLeases" name="RightOfUseAssetAndLeaseLiabilityRecognitionForNewLeases" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AccruedCostOfRevenues" name="AccruedCostOfRevenues" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_InflationReductionActOfTwoThousandTwentyTwoPolicyPolicyTextBlock" name="InflationReductionActOfTwoThousandTwentyTwoPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_WarrantLiability" name="WarrantLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_VendorDeposits" name="VendorDeposits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AlphaSteelMember" name="AlphaSteelMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_EquityMethodInvestmentsFinancialInformationTableTextBlock" name="EquityMethodInvestmentsFinancialInformationTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_LiquidityRatioAmountMinimumLimit" name="LiquidityRatioAmountMinimumLimit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_SunEdisonUtilityHoldingsIncMember" name="SunEdisonUtilityHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_ShortTermNonInterestBearingCustomerAdvance" name="ShortTermNonInterestBearingCustomerAdvance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AssumedExerciseOfWarrantLiability" name="AssumedExerciseOfWarrantLiability" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_HxTrackerMember" name="HxTrackerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AggregateBalanceOfUnrestrictedCash" name="AggregateBalanceOfUnrestrictedCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_DebtInstrumentInitialBorrowingAmount" name="DebtInstrumentInitialBorrowingAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_DebtInstrumentDelayedDrawLoanCommitmentAmount" name="DebtInstrumentDelayedDrawLoanCommitmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" name="AccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_DeferredIncomeTaxes" name="DeferredIncomeTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AccruedExpensesAndOtherCurrentLiabilitiesAbstract" name="AccruedExpensesAndOtherCurrentLiabilitiesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_ClassOfWarrantOrRightAggregatePercentageOfCommonStockOutstanding" name="ClassOfWarrantOrRightAggregatePercentageOfCommonStockOutstanding" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ftci_NewWarrantMember" name="NewWarrantMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_TamaraMullingsMember" name="TamaraMullingsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_SubscriptionRevenueContractTerms" name="SubscriptionRevenueContractTerms" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_PersonnelCostsExpense" name="PersonnelCostsExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_SecondDelayedDrawTermLoansMember" name="SecondDelayedDrawTermLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_PurchaseOfPropertyAndEquipmentIncludedInAccountPayable" name="PurchaseOfPropertyAndEquipmentIncludedInAccountPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_IncreasedInDefaultInterestRate" name="IncreasedInDefaultInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ftci_DebtDiscountAndDeferredDebtCostsBalance" name="DebtDiscountAndDeferredDebtCostsBalance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_TreasuryStock1Member" name="TreasuryStock1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_ScheduleOfOperatingLeaseAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfOperatingLeaseAssetsAndLiabilitiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_ImpactOfAdoption" name="ImpactOfAdoption" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AssessmentMember" name="AssessmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_FirstDelayedDrawTermLoansMember" name="FirstDelayedDrawTermLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_PaidInKindNonCashInterestAddedToSeniorNotesPrincipal" name="PaidInKindNonCashInterestAddedToSeniorNotesPrincipal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_PlcBarclaysBankMember" name="PlcBarclaysBankMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_OutstandingWarrantsMember" name="OutstandingWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_SharesIssuedForLegalSettlement" name="SharesIssuedForLegalSettlement" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_VendorDepositsWithRelatedParty" name="VendorDepositsWithRelatedParty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_RetireAggregateSharesOfCommonStock" name="RetireAggregateSharesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_AggregateOfferingPrice" name="AggregateOfferingPrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_CapitalContributions" name="CapitalContributions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_DebtInstrumentSecondDelayedDrawLoanCommitmentAmount" name="DebtInstrumentSecondDelayedDrawLoanCommitmentAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_ProductWarrantyLife" name="ProductWarrantyLife" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_MajorCustomersMember" name="MajorCustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_SharesIssuedForLegalSettlementAmt" name="SharesIssuedForLegalSettlementAmt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_WarrantsRecoverableFromManufacturer" name="WarrantsRecoverableFromManufacturer" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_WarrantExpirationYears" name="WarrantExpirationYears" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_DescriptionOfRevisedTariffsClassification" name="DescriptionOfRevisedTariffsClassification" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_ImpactOfStockSplit" name="ImpactOfStockSplit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_RevenueRecognizedInExcessOfBillings" name="RevenueRecognizedInExcessOfBillings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_RevenueMinimumCovenantAmount" name="RevenueMinimumCovenantAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_AccountsReceivableAllowanceForCreditLossExpenseReversal" name="AccountsReceivableAllowanceForCreditLossExpenseReversal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AdditionalInterestRateAbovePrime" name="AdditionalInterestRateAbovePrime" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_EBITDAMinimumCovenant" name="EBITDAMinimumCovenant" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_WorkforceActivityAbstract" name="WorkforceActivityAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_ShortTermInterestBearingLoanCustomerDvance" name="ShortTermInterestBearingLoanCustomerDvance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_CostOfAssessment" name="CostOfAssessment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_MinimumBalanceCovenant" name="MinimumBalanceCovenant" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_AmendmentWarrantsMember" name="AmendmentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_TermSheetMember" name="TermSheetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_DeferredCostOfRevenue" name="DeferredCostOfRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_TariffsOnMerchandisePercent" name="TariffsOnMerchandisePercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_TaihuaNewEnergyMember" name="TaihuaNewEnergyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_RecievablesFromRelatedParties" name="RecievablesFromRelatedParties" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_DescriptionOfBusinessLineItems" name="DescriptionOfBusinessLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_IndirectPersonnelCostsExcludingStockBasedCompensation" name="IndirectPersonnelCostsExcludingStockBasedCompensation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_ScheduleOfSeveranceAndTerminationRelatedCostsTableTextBlock" name="ScheduleOfSeveranceAndTerminationRelatedCostsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_FernwehEngagedOperatorCompanyLlcMember" name="FernwehEngagedOperatorCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_SouthLakeOneLlcMember" name="SouthLakeOneLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_PrepaidExpensesAndOtherCurrentAssetsTextBlock" name="PrepaidExpensesAndOtherCurrentAssetsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_CommonStockCapitalSharesReservedForFutureIssuanceValue" name="CommonStockCapitalSharesReservedForFutureIssuanceValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_NetProfitAttributable" name="NetProfitAttributable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_SettlementMember" name="SettlementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_InitialTermLoansFundedMember" name="InitialTermLoansFundedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_DescriptionOfTariffsClassification" name="DescriptionOfTariffsClassification" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_AssetPurchaseAgreementMember" name="AssetPurchaseAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_CbpAssessmentsMember" name="CbpAssessmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock" name="AccruedExpensesAndOtherCurrentLiabilitiesDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_TranslationAndOther" name="TranslationAndOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_StockIssuedDuringPeriodSharesExerciseOfWarrants" name="StockIssuedDuringPeriodSharesExerciseOfWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_PotentialFutureIssuanceOfDebt" name="PotentialFutureIssuanceOfDebt" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_QuarterEndCashBalanceCovenant" name="QuarterEndCashBalanceCovenant" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="ftci_WarrantsReceived" name="WarrantsReceived" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ftci_DayvLlcMember" name="DayvLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AssessmentTypeAxis" name="AssessmentTypeAxis" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="ftci_AbilityToContinueAsAGoingConcern" name="AbilityToContinueAsAGoingConcern" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_ForwardStockSplit" name="ForwardStockSplit" type="xbrli:pureItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="ftci_ProvisionForInventoryObsolescence" name="ProvisionForInventoryObsolescence" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="ftci_PurchaseObligationPercentage" name="PurchaseObligationPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="ftci_UnrestrictedCashCovenant" name="UnrestrictedCashCovenant" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
</xsd:schema>
