Balance Sheets - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 531,213	$ 591,444
Marketable securities	7,635,463	7,591,381
Accounts receivable, net of allowance for doubtful accounts of $20,252 in 2021 and $14,017 in 2020	1,813,346	1,387,698
Inventories (net)	1,410,789	1,415,773
Prepaid expenses and other current assets	192,579	161,208
Prepaid income taxes	0	99,107
Total current assets	11,583,390	11,246,611
Property, plant, and equipment:
Land	69,000	69,000
Factory equipment and fixtures	4,605,742	4,516,335
Building and improvements	2,853,718	2,848,585
Total property, plant and equipment	7,528,460	7,433,920
Less accumulated depreciation	6,869,598	6,760,255
Total property, plant, and equipment, net	658,862	673,665
TOTAL ASSETS	12,242,252	11,920,276
Current liabilities:
Accounts payable	410,894	31,800
Accrued expenses	1,627,390	1,363,457
Deferred revenue	190,164	0
Income taxes payable	88,738	0
Dividends payable	20,575	19,028
Total current liabilities	2,337,761	1,414,285
Deferred income taxes (net)	83,222	151,684
Commitments and contingencies
Stockholders’ equity:
Common stock, $.10 par value; 10,000,000 shares authorized; 4,594,319 shares issued and outstanding at December 31, 2021 and 2020, respectively	459,432	459,432
Retained earnings	9,361,837	9,894,875
Total stockholders’ equity	9,821,269	10,354,307
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 12,242,252	$ 11,920,276