v3.22.2
Balance Sheet Components
 6 Months Ended
Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Balance Sheet Components Balance Sheet Components
Inventory
As of June 30, 2022, inventory consisted of finished goods of $15.9 million and work-in-progress of $0.6 million. As of December 31, 2021, inventory consisted of finished goods.
Property and Equipment, net:    
June 30, 2022December 31, 2021
 (in thousands)
Machinery and equipment
$12,721 $10,573 
Construction in progress
5,604 3,657 
Computer and office equipment
909 916 
Leasehold improvements
1,631 503 
Furniture and fixtures
307 309 
21,172 15,958 
Less: Accumulated depreciation and amortization
(8,362)(6,966)
$12,810 $8,992 
            
As of June 30, 2022, construction in progress pertains to the cost of individual components of a custom instrument set used for surgical placement of the Company's products that have not yet been placed into service of $3.8 million and construction costs related to the new lease in Santa Clara of $1.8 million. Depreciation expense was $0.8 million and $0.5 million for the three months ended June 30, 2022 and 2021, respectively, and $1.5 million and $0.8 million for the six months ended June 30, 2022 and 2021, respectively.
Accrued Liabilities and Other:
June 30, 2022December 31, 2021
 (in thousands)
Accrued compensation and related expenses$7,927 $10,055 
    Accrued professional services 652 995 
Others1,610 1,303 
$10,189 $12,353 
Accounts Receivable and Allowance for Credit Losses:
The movement in the allowance for credit losses was as follows:
June 30, 2022December 31, 2021
 (in thousands)
Balance at beginning of year$264 $263 
Provision— 14 
Write-offs(9)(13)
Balance at end of year$255 $264