CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Aug. 31, 2020	May 31, 2020
Current Assets:
Cash and cash equivalents	$ 6,964,314	$ 8,641,027
Accounts receivable, less allowance for doubtful accounts of $272,356 and $70,981 as of August 31, 2020 and May 31, 2020, respectively	1,583,420	1,765,871
Inventories, net	4,101,404	2,850,836
Prepaid expenses and other	470,934	1,509,083
Total current assets	13,120,072	14,766,817
Property and Equipment, net of accumulated depreciation and amortization of $1,894,375 and $1,867,643 as of August 31, 2020 and May 31, 2020, respectively	292,235	279,379
Right of Use Assets, net of accumulated amortization of $288,746 and $231,489 as of August 31, 2020 and May 31, 2020, respectively	1,654,253	1,711,510
Investments	165,324	165,324
Intangible Assets, net of accumulated amortization of $501,962 and $496,124 as of August 31, 2020 and May 31, 2020, respectively	215,975	168,655
Other Assets	444,631	168,193
Total Assets	15,892,490	17,259,878
Current Liabilities:
Accounts payable and accrued expenses	1,270,913	986,711
Accrued compensation	309,345	278,627
Lease liability, current portion	221,201	211,809
Total current liabilities	1,801,459	1,477,147
Lease Liability, net of current portion	1,510,406	1,569,678
Total Liabilities	3,311,865	3,046,825
Commitments and Contingencies (Notes 5 and 6)
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, 321,429 issued and outstanding at August 31, 2020 and May 31, 2020 and Preferred stock, undesignated, no par value,4,428,571 shares authorized, none issued and outstanding at August 31, 2020 and May 31, 2020	25,714	25,714
Common stock, $0.08 par value, 25,000,000 shares authorized, 11,752,589 and 11,740,089 issued and outstanding at August 31, 2020 and May 31, 2020, respectively	940,205	939,205
Additional paid-in-capital	35,231,415	35,213,707
Accumulated other comprehensive loss	(41,562)	(39,841)
Accumulated deficit	(23,575,147)	(21,925,732)
Total Shareholders' Equity	12,580,625	14,213,053
Total Liabilities and Shareholders' Equity	15,892,490	17,259,878
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, 321,429 issued and outstanding at August 31, 2020 and May 31, 2020 and Preferred stock, undesignated, no par value,4,428,571 shares authorized, none issued and outstanding at August 31, 2020 and May 31, 2020	25,714	25,714
Preferred Stock [Member]
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, 321,429 issued and outstanding at August 31, 2020 and May 31, 2020 and Preferred stock, undesignated, no par value,4,428,571 shares authorized, none issued and outstanding at August 31, 2020 and May 31, 2020