CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	3 Months Ended
	Aug. 31, 2013	Aug. 31, 2012
Cash flows from operating activities:
Net (loss) income	$ (167,714)	$ 291,640
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities
Depreciation and amortization	50,235	54,167
Change in provision for losses on accounts receivable	4,675	2,730
Inventory reserve	(6,713)	24,780
Stock option expense	881
Decrease in deferred rent liability	(1,656)	(108)
Changes in assets and liabilities:
Accounts receivable	(36,264)	(175,667)
Inventories	(213,509)	(24,457)
Prepaid expenses and other assets	15,527	(3,760)
Accounts payable and other accrued expenses	(25,609)	89,033
Accrued compensation	3,876	72,047
Net cash (used in) provided by operating activities	(376,271)	330,405
Cash flows from investing activities:
Purchases of property and equipment	(8,731)	(65,186)
Net cash used in investing activities	(8,731)	(65,186)
Cash flows from financing activities:
Exercise of stock options	760
Payments on line of credit or equipment loan		(43,000)
Net cash provided by (used in) financing activities	760	(43,000)
Effect of exchange rate changes in cash	(91)	(81)
Net (decrease) increase in cash and cash equivalents	(384,333)	222,138
Cash and cash equivalents at beginning of period	2,469,796	1,077,342
Cash and cash equivalents at end of period	2,085,463	1,299,480
Supplemental Disclosure of Cash-Flow Information:
Interest		308
Income taxes	$ 1,750	$ 61,540