SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($)	12 Months Ended
May 31, 2019	May 31, 2018
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Cash, Uninsured Amount	$ 406,000
Property, Plant and Equipment, Net	351,070	$ 351,149
Inventory Valuation Reserves	49,000	43,000
Depreciation, Depletion and Amortization	101,216	111,055
Amortization of Intangible Assets	$ 61,689	75,546
Equity Method Investment, Ownership Percentage	6.00%
Research and Development Expense	$ 1,679,098	1,398,368
Deferred Tax Assets, Valuation Allowance, Current	2,143,000
Advertising Expense	$ 0	$ 1,000
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
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
Customer Concentration Risk [Member] \| Revenue Benchmark [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	46.30%	43.30%
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	68.10%	53.30%
One Vendor [Member] \| Supplier Concentration Risk [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	23.80%
One Vendor [Member] \| Accounts Payable [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage	32.10%	29.10%
Two Vendor [Member] \| Supplier Concentration Risk [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Concentration Risk, Percentage		27.70%
Share-based Payment Arrangement, Option [Member]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in Shares)	1,476,209	1,138,625
MEXICO
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) [Line Items]
Inventory, Gross	$ 665,000	$ 657,000
Property, Plant and Equipment, Net	$ 39,000	$ 41,000

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of valuation allowance of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as current.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Amount of valuation reserve for inventory.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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