Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 14,487	$ 23,379
Accounts receivable, net	5,799	7,522
Inventory	7,863	9,097
Prepaid expenses and other current assets	539	688
Total current assets	28,688	40,686
Property and equipment, net	3,479	4,286
Right-of-use assets	3,132
Other assets	73	73
Total assets	35,372	45,045
Current liabilities:
Accounts payable	2,873	2,637
Accrued liabilities	2,727	5,001
Current portion of long-term debt	670	5,977
Operating lease liabilities	1,582
Other liabilities	42
Total current liabilities	7,894	13,615
Long-term debt, net of current portion	7,149	6,509
Operating lease liabilities, net of current portion	1,840
Total liabilities	16,883	20,124
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 December 31, 2019 and December 31, 2018
Common stock, $0.0001 par value per share; 100,000,000 shares authorized; 18,081,753 and 17,095,456 shares issued and outstanding as of December 31, 2019 and December 31, 2018	2	2
Additional paid-in capital	167,149	158,912
Accumulated deficit	(148,662)	(133,993)
Total stockholders’ equity	18,489	24,921
Total liabilities and stockholders’ equity	$ 35,372	$ 45,045