Consolidated Statements of Operations (USD $)	3 Months Ended		6 Months Ended
	May 31, 2012	May 31, 2011	May 31, 2012	May 31, 2011
Net sales	$ 11,685,169	$ 7,845,150	$ 17,997,383	$ 12,509,488
Cost of goods sold	8,527,545	5,889,162	13,363,538	10,077,665
Gross profit	3,157,624	1,955,988	4,633,845	2,431,823
Expenses:
Engineering	73,351	120,333	158,411	238,642
Selling	424,528	472,404	791,312	873,012
General and administrative	1,165,979	815,076	1,828,101	1,430,950
Total expenses	1,663,858	1,407,813	2,777,824	2,542,604
Income (loss) from operations	1,493,766	548,175	1,856,021	(110,781)
Other income (expense):
Interest expense	(109,026)	(105,506)	(202,069)	(201,708)
Other	19,738	5,235	39,604	31,304
Total other income (loss)	(89,288)	(100,271)	(162,465)	(170,404)
Income (loss) before income taxes	1,404,478	447,904	1,693,556	(281,185)
Current tax expense (benefit)	468,497	157,155	564,077	(87,357)
Net income (loss)	$ 935,981	$ 290,749	$ 1,129,479	$ (193,828)
Net income per share:
Basic net income (loss) per share (in Dollars per share)	$ 0.23	$ 0.07	$ 0.28	$ (0.05)
Diluted net income (loss) per share (in Dollars per share)	$ 0.23	$ 0.07	$ 0.28	$ (0.05)
Weighted average outstanding shares used to compute basic net income per share (in Shares)	4,031,439	4,017,852	4,029,825	4,014,102
Weighted average outstanding shares used to compute diluted net income per share (in Shares)	4,047,787	4,047,678	4,047,346	4,014,102