INCOME TAXES (Details) - Deferred Tax - USD ($)	May 31, 2020	May 31, 2019
Deferred tax assets:
Accounts receivable, principally due to allowance for doubtful accounts	$ 17,000	$ 18,000
Inventory valuation	16,000	12,000
Compensated absences	64,000	48,000
Net operating loss carryforwards	2,286,000	1,735,000
Tax credit carryforwards	599,000	467,000
Deferred rent expense/Capitalized leases	17,000	9,000
Other	171,000	176,000
Accumulated depreciation and amortization	5,000	(6,000)
Total deferred tax assets	3,175,000	2,459,000
Less valuation allowance	(3,175,000)	(2,459,000)
Net deferred tax asset

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accumulated depreciation and amortization.

+ References

No definition available.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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Amount, before allocation of a valuation allowances, of deferred tax assets attributable to deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days).

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from the allowance for doubtful accounts.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred rent.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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