Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 13,950	$ 14,487
Accounts receivable, net	6,320	5,799
Inventory	7,944	7,863
Prepaid expenses and other current assets	518	539
Total current assets	28,732	28,688
Property and equipment, net	3,077	3,479
Right-of-use assets	2,770	3,132
Other assets	73	73
Total assets	34,652	35,372
Current liabilities:
Accounts payable	1,761	2,873
Accrued liabilities	1,965	2,727
Current portion of long-term debt	1,271	670
Operating lease liabilities	1,613	1,582
Other liabilities	34	42
Total current liabilities	6,644	7,894
Long-term debt, net of current portion	6,621	7,149
Operating lease liabilities, net of current portion	1,426	1,840
Total liabilities	14,691	16,883
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value per share; 5,000,000 shares authorized; no shares issued and outstanding as of March 31, 2020 and December 31, 2018
Common stock, $0.0001 par value per share; 100,000,000 shares authorized; 18,638,555 and 18,081,753 shares issued and outstanding as of March 31, 2020 and December 31, 2019	2	2
Additional paid-in capital	170,353	167,149
Accumulated deficit	(150,394)	(148,662)
Total stockholders’ equity	19,961	18,489
Total liabilities and stockholders’ equity	$ 34,652	$ 35,372