INCOME TAXES (Details) - Deferred Tax - USD ($)	May 31, 2021	May 31, 2020
Deferred tax assets:
Accounts receivable, principally due to allowance for doubtful accounts	$ 200,000	$ 17,000
Inventory valuation	387,000	16,000
Compensated absences	85,000	64,000
Net operating loss carryforwards	3,195,000	2,286,000
Tax credit carryforwards	1,055,000	599,000
Deferred rent expense/Capitalized leases	14,000	17,000
Stock Options	299,000	181,000
Losses of foreign subsidiaries & Other, net	370,000	303,000
Accumulated depreciation and amortization	(15,000)	5,000
Total deferred tax assets	5,590,000	3,488,000
Less valuation allowance	(5,590,000)	(3,488,000)
Net deferred tax asset