Statements of Comprehensive Income (Loss) (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
Net sales	$ 7,458,050	$ 6,962,065	$ 15,003,482	$ 14,227,580
Cost of sales	6,251,233	6,248,604	12,443,567	12,386,745
Gross profit	1,206,817	713,461	2,559,915	1,840,835
Selling, general and administrative expenses	1,186,168	945,478	2,180,990	1,860,104
Operating income (loss)	20,649	(232,017)	378,925	(19,269)
Other income
Interest income	1,716	1,753	3,312	16,970
Other	10,105	13,734	28,076	16,861
Total other income	11,821	15,487	31,388	33,831
Income (loss) before provision (benefit) for income taxes	32,470	(216,530)	410,313	14,562
Provision (benefit) for income taxes	11,269	(35,524)	83,051	5,745
Net income (loss)	21,201	(181,006)	327,262	8,817
Other comprehensive income, net of tax:
Unrealized gain on investment securities		2,712		1,038
Total comprehensive income (loss)	$ 21,201	$ (178,294)	$ 327,262	$ 9,855
Net income (loss) per share:
Basic	$ 0.01	$ (0.08)	$ 0.14	$ 0.00
Diluted	$ 0.01	$ (0.08)	$ 0.14	$ 0.00
Weighted average number of shares outstanding:
Basic	2,429,051	2,402,665	2,426,159	2,402,649
Diluted	2,429,199	2,402,665	2,426,233	2,404,043
Dividends per share:		$ 0.25		$ 0.50