CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($)	3 Months Ended
	Aug. 31, 2018	Aug. 31, 2017
Cash flows from operating activities:
Net loss	$ (451,740)	$ (207,059)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	43,960	48,833
Change in provision for losses on accounts receivable	5,697	7,514
Inventory reserve	715	(8)
Stock option expense	8,084	4,383
Increase in deferred rent liability	3,333	5,563
Changes in assets and liabilities:
Accounts receivable	(219,444)	5,202
Inventories	(30,395)	(62,379)
Prepaid expenses and other assets	(14,259)	(19,053)
Accounts payable and accrued expenses	(107,313)	82,480
Accrued compensation	4,704	9,810
Net cash used in operating activities	(756,658)	(124,714)
Cash flows from investing activities:
Increase in intangibles	(22,524)
Purchases of property and equipment	(38,081)	(19,974)
Net cash used in investing activities	(60,605)	(19,974)
Cash flows from financing activities:
Proceeds from sale of common stock, net	179,504
Exercise of stock options	17,875	1,038
Net cash provided by financing activities	197,379	1,038
Effect of exchange rate changes in cash	(1,326)	(824)
Net decrease in cash and cash equivalents	(621,210)	(144,474)
Cash and cash equivalents at beginning of period	1,204,903	1,225,462
Cash and cash equivalents at end of period	583,693	1,080,988
Cash paid during the period for:
Interest	$ 47