Significant Accounting Policies (Tables)

3 Months Ended

Aug. 31, 2013

Accounting Policies [Abstract]

Schedule of Inventory, Current [Table Text Block]

	August 31,		May 31,
	2013		2013
Raw materials	$	908,000	$	787,000
Work in progress		620,000		555,000
Finished products		263,000		229,000
Total	$	1,791,000	$	1,571,000

Schedule of Share-based Compensation, Activity [Table Text Block]

		Exercise
		Price
	Option	Weighted
	Shares	Average
Outstanding May 31, 2013	846,500	$0.47
Granted	20,000	$0.83
Exercised	(2,000)	$0.38
Cancelled or expired	--	--
Outstanding August 31, 2013	864,500	$0.48

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Three Months
	Ended
	August 31,
		2013		2012
Numerator:
(Loss) income from continuing operations	$	(167,714)	$	291,640
Denominator for basic net income per common share		7,280,866		6,952,339
Effect of dilutive securities:
Options		--		350,795
Denominator for diluted net (loss) income per common share		7,280,866		7,303,134
Basic net (loss) income per common share	$	(0.02)	$	0.04
Diluted net (loss) income per common share	$	(0.02)	$	0.04