Statements of Comprehensive Income - USD ($)	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net sales	$ 32,517,883	$ 22,521,012
Cost of sales	24,855,631	17,806,444
Gross profit	7,662,252	4,714,568
Selling, general and administrative expenses	3,808,395	3,188,112
Operating Income	3,853,857	1,526,456
Other income
Interest income	160,650	88,836
Other	54,569	36,113
Total other income	215,219	124,949
Income before provision for income taxes	4,069,076	1,651,405
Provision for income taxes	993,279	515,669
Net income	3,075,797	1,135,736
Other comprehensive income, net of tax:
Unrealized loss on investment securities	(2,750)	(2,191)
Total comprehensive income	$ 3,073,047	$ 1,133,545
Net income per share:
Basic	$ 1.32	$ 0.49
Diluted	$ 1.31	$ 0.49
Weighted average number of shares outstanding:
Basic	2,333,885	2,312,870
Diluted	2,348,307	2,324,838