Statements of Comprehensive Income - USD ($)	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net sales	$ 31,526,231	$ 36,477,851
Cost of sales	25,967,616	29,414,678
Gross profit	5,558,615	7,063,173
Selling, general and administrative expenses	4,386,307	4,410,234
Operating Income	1,172,308	2,652,939
Other income
Interest income	109,749	167,682
Other	27,132	61,012
Total other income	136,881	228,694
Income before provision for income taxes	1,309,189	2,881,633
Provision for income taxes	145,521	538,939
Net income	1,163,668	2,342,694
Other comprehensive income, net of tax:
Unrealized (loss) gain on investment securities	(1,808)	5,050
Total comprehensive income	$ 1,161,860	$ 2,347,744
Net income per share:
Basic	$ 0.49	$ 0.99
Diluted	$ 0.49	$ 0.98
Weighted average number of shares outstanding:
Basic	2,393,207	2,372,945
Diluted	2,396,618	2,389,228