CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	6 Months Ended
Nov. 30, 2014	Nov. 30, 2013
Cash flows from operating activities:
Net loss	$ (457,296)us-gaap_NetIncomeLoss	$ (411,072)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash provided by (used in) operating activities
Depreciation and amortization	126,176us-gaap_DepreciationAndAmortization	97,352us-gaap_DepreciationAndAmortization
Stock option expense	1,804us-gaap_StockOptionPlanExpense	881us-gaap_StockOptionPlanExpense
Change in provision for losses on accounts receivable	(16,659)us-gaap_ProvisionForDoubtfulAccounts	4,675us-gaap_ProvisionForDoubtfulAccounts
Inventory reserve	7,423	(6,713)
Gain on disposal of equipment	(665)
Decrease in deferred rent liability	(9,262)	(6,418)
Changes in assets and liabilities:
Accounts receivable	900,454	45,414
Inventories	(231,601)us-gaap_IncreaseDecreaseInInventories	(321,700)us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other assets	(56,787)	10,316
Accounts payable and other accrued expenses	(88,082)	(65,525)
Accrued compensation	8,491	(87,358)
Net cash provided by (used in) operating activities	183,996	(740,148)
Cash flows from investing activities:
Purchases of property and equipment	(8,654)us-gaap_RepaymentsOfLinesOfCredit	(83,855)us-gaap_RepaymentsOfLinesOfCredit
Proceeds from sales of equipment	1,900
Increase in intangibles	(14,136)
Net cash used in investing activities	(20,890)	(83,855)
Cash flows from financing activities:
Proceeds from exercise of stock options	3,495	1,780
Net cash provided by financing activities	3,495	1,780
Effect of exchange rate changes in cash	(1,678)	(14)
Net increase in cash and cash equivalents	164,923	(822,237)
Cash and cash equivalents at beginning of period	1,509,125	2,469,796
Cash and cash equivalents at end of period	1,674,048	1,647,559
Cash paid during the period for:
Interest	17us-gaap_InterestPaid	0us-gaap_InterestPaid
Income taxes	$ 0us-gaap_IncomeTaxesPaid	$ 3,500us-gaap_IncomeTaxesPaid

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The increase (decrease) during the period in the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.