Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating Activities
Net income (loss)	$ (203,400)	$ 114,800
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation and amortization	8,500	6,100
Other assets	104,300	105,100
Other liabilities	(18,100)	(17,500)
Adjustments To Reconcile Net Income Loss To Cash	(108,700)	208,500
(Increase) decrease in assets
Accounts receivable	171,700	113,200
Inventory	(88,400)	(59,900)
Prepaid and other	79,100	34,200
Increase in liabilities
Accounts payable and accrued expenses	116,500	62,100
Income taxes		7,300
Total (increase) decrease in assets and liabilities	278,900	156,900
Net cash provided by operating activities	170,200	365,400
Increase in cash	170,200	365,400
Cash at beginning of year	1,846,700	1,362,800
Cash at end of period	$ 2,016,900	$ 1,728,200