Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 7,646	$ 6,713
Treasury Bills	1,980	3,000
Equity securities	56	56
Trade receivables, less allowance for doubtful accounts of $11	1,161	1,005
Inventories	1,745	1,663
Other current assets	214	188
Income tax receivable	11	3
Total current assets	12,813	12,628
Deferred income tax asset	256	208
Intangible assets, net	0	38
Property and equipment, net	975	1,017
Total assets	14,044	13,891
Current liabilities
Current maturity of financing lease	6	6
Accounts payable	274	349
Accrued expenses	350	342
Total current liabilities	630	697
Long-term liabilities
Financing lease, net of current maturities	0	6
Total long-term liabilities	0	6
Commitments and contingencies
Stockholders' equity
Common stock par value $0.10 per share; authorized 10,000,000 shares; 3,428,021 and 3,395,521 shares issued and outstanding, respectively	342	339
Additional paid-in capital	2,163	2,041
Retained earnings	10,908	10,808
Accumulated other comprehensive income (unrealized income on available-for-sale securities, net of income tax)	1	0
Total stockholders' equity	13,414	13,188
Total liabilities and stockholders' equity	$ 14,044	$ 13,891