Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 6,713	$ 1,090
Treasury Bills	3,000	7,999
Equity securities	56	42
Trade receivables, less allowance for doubtful accounts of $11	1,005	957
Inventories	1,663	1,572
Other current assets	188	170
Income tax receivable	3	26
Total current assets	12,628	11,856
Deferred income tax asset	208	246
Intangible assets, net	38	228
Property and equipment, net	1,017	989
Total assets	13,891	13,319
Current liabilities
Current maturity of financing lease	6	6
Accounts payable	349	197
Accrued expenses	342	330
Total current liabilities	697	533
Long-term liabilities
Financing lease, net of current maturities	6	12
Total long-term liabilities	6	12
Commitments and contingencies
Stockholders' equity
Common stock par value $0.10 per share; authorized 10,000,000 shares; 3,395,521 shares issued and outstanding	339	339
Additional paid-in capital	2,041	2,036
Retained earnings	10,808	10,398
Accumulated other comprehensive gain (unrealized gain on available-for-sale securities, net of income tax)	0	1
Total stockholders' equity	13,188	12,774
Total liabilities and stockholders' equity	$ 13,891	$ 13,319