Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 3,138	$ 3,515
Accounts receivable, net	3,737	3,966
Unbilled accounts receivable	470	155
Inventories	8,821	8,832
Prepaid expenses and other current assets	1,344	1,130
Total current assets	17,510	17,598
Equipment, furniture and leasehold improvements, net	7,926	8,100
Operating lease right - of - use assets	3,545	3,729
Intangibles and other assets	133	160
Total assets	29,114	29,587
Current liabilities:
Accounts payable	1,577	1,302
Accrued compensation	1,566	1,778
Revolving credit facility, net	2,191	2,891
Common stock warrant liability	43	23
Other accrued expenses	1,485	1,401
Deferred revenue	294	277
Operating lease liability - current	791	775
Other current liabilities	351	342
Total current liabilities	8,298	8,789
Finance lease liability - long term	20	24
Operating lease liability - long term	2,863	3,067
Total liabilities	11,181	11,880
Commitments and contingencies
Shareholders' equity:
Preferred stock, $.001 par value: authorized 10,000,000 shares: Series B Convertible Preferred stock, (liquidation preference of $5,659) stated value $1,000 per share, $.001 par value: 10,000 shares designated and 5,659 issued and outstanding as of March 31, 2020 and December 31, 2019.
Common stock, $.001 par value: authorized 200,000,000 shares, issued 53,980,918 shares, outstanding 53,818,852 shares as of March 31, 2020 and issued 50,250,378 shares, outstanding 50,088,312 shares as of December 31, 2019.	54	50
Additional paid-in capital	260,358	258,767
Accumulated deficit	(241,979)	(240,610)
Treasury stock, 162,066 shares as of March 31, 2020 and December 31, 2019.	(500)	(500)
Total shareholders' equity	17,933	17,707
Total liabilities and shareholders' equity	$ 29,114	$ 29,587