SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	12 Months Ended
	May 31, 2020	May 31, 2019
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Cash, Uninsured Amount	$ 8,595,241
Other Receivables, Gross, Current	1,836,852	$ 1,527,762
Property, Plant and Equipment, Net	$ 279,379	351,070
Threshold Period Past Due for Write-off of Trade Accounts Receivable	90 days
Inventory Valuation Reserves	$ 67,000	49,000
Depreciation, Depletion and Amortization	105,299	101,216
Amortization of Intangible Assets	$ 23,873	61,689
Equity Method Investment, Ownership Percentage	6.00%
Research and Development Expense	$ 1,910,209	1,679,098
Deferred Tax Assets, Valuation Allowance	3,175,000	2,459,000
Deferred Tax Assets, Gross	3,175,000	2,459,000
Advertising Expense	174	0
Operating Lease, Right-of-Use Asset	$ 1,711,510
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)	1,789,251	1,476,209
Minimum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Maximum [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Distribution Rights [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	18 years
Purchased Technology Rights [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Patents [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
MEXICO
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Inventory, Gross	$ 613,000	$ 665,000
Property, Plant and Equipment, Net	31,000	$ 39,000
Accounting Standards Update 2016-02 [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Operating Lease, Right-of-Use Asset	1,942,999
Operating Lease, Liability	$ 1,980,970
Three Distributors [Member] | Revenue Benchmark [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	57.20%
Three Distributors [Member] | Accounts Receivable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	80.00%
Two Distributors [Member] | Revenue Benchmark [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage		46.30%
Two Distributors [Member] | Accounts Receivable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage		68.10%
One Distributors [Member] | Revenue Benchmark [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	25.70%	36.30%
Distributors in Ecuador [Member] | Accounts Receivable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	43.90%
Supplier Concentration Risk [Member] | Cost of Goods and Service, Product and Service Benchmark [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	59.30%	23.80%
5% Convertible Preferred Stock [Member] | Common Stock [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Convertible Preferred Stock, Shares Issued upon Conversion (in Shares)	321,429