Summary of Significant Accounting Policies (Tables)

9 Months Ended

Feb. 28, 2015

Accounting Policies [Abstract]

Schedule of Inventory, Current [Table Text Block]

		February 28,		May 31,
		2015		2014
Raw materials	$	1,009,000	$	899,000
Work in progress		898,000		635,000
Finished products		204,000		232,000
Total	$	2,111,000	$	1,766,000

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

			Exercise
			Price
	Option		Weighted
	Shares		Average
Outstanding May 31, 2014	860,500	$	0.51
Granted	356,000		0.82
Exercised	(11,000)		0.40
Cancelled or expired	(35,500)		0.73
Outstanding February 28, 2015	1,170,000	$	0.60

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

	Nine Months				Three Months
	Ended				Ended
	February 28,				February 28,
	2015		2014		2015		2014
Numerator:
(Loss)income from continuing operations	$	(574,483)	$	(384,532)	$	(117,193)	$	26,544
Denominator for basic net(loss) income Per common share		7,551,447		7,310,872		7,554,603		7,378,403
Effect of dilutive securities:
Options and warrants		--		--		--		352,849
Denominator for diluted net (loss)income per common share		7,551,447		7,310,872		7,554,603		7,731,252
Basic net (loss) income per common share	$	(0.08)	$	(0.05)	$	(0.02)	$	0.00
Diluted net (loss) income per common share	$	(0.08)	$	(0.05)	$	(0.02)	$	0.00