Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2012	Aug. 31, 2011
Net sales	$ 11,533,882	$ 9,252,063	$ 29,531,268	$ 21,761,551
Cost of goods sold	8,109,820	6,544,644	21,473,360	16,622,309
Gross profit	3,424,062	2,707,419	8,057,908	5,139,242
Expenses:
Engineering	82,044	91,840	240,455	330,482
Selling	468,228	447,103	1,259,539	1,320,115
General and administrative	1,267,267	730,569	3,095,370	2,161,519
Total expenses	1,817,539	1,269,512	4,595,364	3,812,116
Income (loss) from operations	1,606,523	1,437,907	3,462,544	1,327,126
Other income (expense):
Interest expense	(129,751)	(120,200)	(331,817)	(321,910)
Other	18,403	46,523	58,005	77,821
Total other income (loss)	(111,348)	(73,677)	(273,812)	(244,089)
Income (loss) before income taxes	1,495,175	1,364,230	3,188,732	1,083,037
Current tax expense (benefit)	515,724	344,390	1,079,803	257,035
Net income (loss)	$ 979,451	$ 1,019,840	$ 2,108,929	$ 826,002
Net income per share:
Basic net income (loss) per share (in Dollars per share)	$ 0.24	$ 0.25	$ 0.52	$ 0.21
Diluted net income (loss) per share (in Dollars per share)	$ 0.24	$ 0.25	$ 0.52	$ 0.20
Weighted average outstanding shares used to compute basic net income per share (in Shares)	4,035,852	4,019,874	4,031,828	4,016,039
Weighted average outstanding shares used to compute diluted net income per share (in Shares)	4,052,246	4,042,135	4,049,236	4,049,706