Condensed Balance Sheets - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 2,000	$ 16,647
Short-term investments	35,000	24,994
Accounts receivable, net	2,212	1,871
Inventories, net	3,580	2,655
Prepaid expenses and other current assets	769	760
Total current assets	43,561	46,927
Property and equipment, net	463	357
Operating lease right-of-use asset, net	114	139
Intangible assets, net	1,404	1,397
Other assets, net	8	13
Total assets	45,550	48,833
Current Liabilities:
Accounts payable	2,400	1,232
Accrued liabilities	593	721
Customer deposits	5	2
Deferred revenue	172	16
Operating lease liability - short term	91	94
Note payable to bank - short term	175	275
Total current liabilities	3,436	2,340
Operating lease liability - long term	32	56
Business acquisition liability - long term	23	23
Total long-term liabilities	55	79
Total liabilities	3,491	2,419
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock - 5,000,000 authorized; par value $0.0001 per share; none issued and outstanding	0	0
Common stock - 150,000,000 authorized; par value $0.0001 per share; 37,711,698 and 37,554,162 shares issued and outstanding each period, respectively	4	4
Additional paid-in capital	72,777	71,705
Accumulated deficit	(30,739)	(25,310)
Accumulated other comprehensive gain	17	15
Total stockholders' equity	42,059	46,414
Total liabilities and stockholders' equity	$ 45,550	$ 48,833