CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Feb. 29, 2020	May 31, 2019
Current Assets:
Cash and cash equivalents	$ 2,391,732	$ 686,785
Accounts receivable, less allowance for doubtful accounts of $76,681 and $73,110 as of February 29, 2020 and May 31, 2019, respectively	962,321	1,454,652
Inventories, net	2,187,605	2,151,090
Prepaid expenses and other	197,505	202,402
Total current assets	5,739,163	4,494,929
Property and Equipment, net of accumulated depreciation and amortization of $1,688,685 and $1,762,344 as of February 29, 2020 and May 31, 2019, respectively	301,153	351,070
Right of Use Assets, net of amortization	1,767,938
Investments	165,324	165,324
Intangible Assets, net	114,011	107,209
Other Assets	127,521	126,832
Total Assets	8,215,110	5,245,364
Current Liabilities:
Accounts payable and accrued expenses	1,267,662	1,037,565
Accrued compensation	236,043	226,829
Equity financing deposit-officer	200,000
Lease liability, current portion	206,127
Total current liabilities	1,909,832	1,264,394
Lease Liability, net of current portion	1,624,358
Total Liabilities	3,534,190	1,264,394
Commitments and Contingencies (Note 6 and 7)
Shareholders' Equity:
Preferred stock, Series A 5% convertible,$0.08 par value, 571,429 shares authorized, issued and outstanding at February 29, 2020 and no shares authorized, issued and outstanding at May 31 2019 and Preferred stock, undesignated, no par value, authorized 4,428,571 and 5,000,000 shares, at February 29, 2020 and none at May 31,2019, respectively and none issued and outstanding at February 29, 2020 and May 31, 2019	45,714
Common stock, $0.08 par value authorized 25,000,000 shares, issued and outstanding 10,310,355 and 9,677,188 at February 29, 2020 and May 31, 2019, respectively	824,827	774,173
Additional paid-in-capital	26,446,538	22,830,006
Common stock subscribed	(1,156,311)
Accumulated other comprehensive loss	(40,688)	(36,531)
Accumulated deficit	(21,439,160)	(19,586,678)
Total Shareholders' Equity	4,680,920	3,980,970
Total Liabilities and Shareholders' Equity	8,215,110	5,245,364
5% Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
Shareholders' Equity:
Preferred stock, Series A 5% convertible,$0.08 par value, 571,429 shares authorized, issued and outstanding at February 29, 2020 and no shares authorized, issued and outstanding at May 31 2019 and Preferred stock, undesignated, no par value, authorized 4,428,571 and 5,000,000 shares, at February 29, 2020 and none at May 31,2019, respectively and none issued and outstanding at February 29, 2020 and May 31, 2019	45,714
Preferred Stock [Member]
Shareholders' Equity:
Preferred stock, Series A 5% convertible,$0.08 par value, 571,429 shares authorized, issued and outstanding at February 29, 2020 and no shares authorized, issued and outstanding at May 31 2019 and Preferred stock, undesignated, no par value, authorized 4,428,571 and 5,000,000 shares, at February 29, 2020 and none at May 31,2019, respectively and none issued and outstanding at February 29, 2020 and May 31, 2019