Statements of Comprehensive Income - USD ($)	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Income Statement [Abstract]
Net sales	$ 27,471,365	$ 26,831,705
Cost of sales	20,099,683	19,690,132
Gross profit	7,371,682	7,141,573
Selling, general and administrative expenses	3,028,449	2,711,807
Operating Income	4,343,233	4,429,766
Other income
Interest income	33,782	36,424
Other	85,492	31,626
Total other income	119,274	68,050
Income before provision for income taxes	4,462,507	4,497,816
Provision for income taxes	1,286,706	1,314,689
Net income	3,175,801	3,183,127
Other comprehensive income, net of tax:
Unrealized gain/(loss) on investment securities	2,978	(2,949)
Total comprehensive income	$ 3,178,779	$ 3,180,178
Net income per share:
Basic	$ 1.39	$ 1.40
Diluted	$ 1.38	$ 1.39
Weighted average number of shares outstanding:
Basic	2,285,686	2,271,426
Diluted	2,302,034	2,290,542