Condensed Statements Of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statements of Comprehensive Income (Loss) [Abstract]
Net sales	$ 2,564	$ 2,462	$ 4,699	$ 4,363
Cost of goods sold	1,156	1,086	2,125	1,997
Gross profit	1,408	1,376	2,574	2,366
Operating expenses
Selling and marketing	427	364	873	712
General and administrative	1,125	458	1,628	901
Research and development	221	283	452	486
Total operating expenses	1,773	1,105	2,953	2,099
Operating income (loss)	(365)	271	(379)	267
Non-operating income
Interest income	7	0	8	2
Total non-operating income, net	7	0	8	2
Income (loss) before income tax expense (benefit)	(358)	271	(371)	269
Income tax expense (benefit)	(74)	57	(78)	57
Net income (loss)	(284)	214	(293)	212
Other comprehensive gain (loss)
Change in unrealized value of available-for-sale securities, net of income tax	2	(1)	2	(1)
Other comprehensive gain (loss)	2	(1)	2	(1)
Net comprehensive income (loss)	$ (282)	$ 213	$ (291)	$ 211
Basic
Net income (loss) per share	$ (0.08)	$ 0.06	$ (0.09)	$ 0.06
Weighted average shares	3,395,521	3,395,521	3,395,521	3,395,521
Diluted
Net income (loss) per share	$ (0.08)	$ 0.06	$ (0.09)	$ 0.06
Weighted average shares	3,395,521	3,413,444	3,395,521	3,433,609