CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Feb. 28, 2022	May 31, 2021
Current Assets:
Cash and cash equivalents	$ 10,173,808	$ 4,199,311
Accounts receivable, less allowance for doubtful accounts of $20,293 and $837,415 as of February 28, 2022 and May 31, 2021, respectively	1,158,738	1,455,051
Inventories, net	3,231,430	3,206,255
Prepaid expenses and other	667,129	370,290
Total current assets	15,231,105	9,230,907
Property and equipment, net of accumulated depreciation and amortization of $2,046,612 and $1,972,357 as of February 28, 2022 and May 31, 2021, respectively	263,048	310,520
Right of use assets, net of accumulated amortization of $658,773 and $469,077 as of February 28, 2022 and May 31, 2021, respectively	1,367,863	1,553,081
Investments	165,324	165,324
Intangible assets, net of accumulated amortization of $49,253 and $126,769 as of February 28, 2022 and May 31, 2021, respectively	386,013	294,830
Other assets	146,980	264,151
Total Assets	17,560,333	11,818,813
Current Liabilities:
Accounts payable and accrued expenses	2,608,840	583,380
Accrued compensation	537,284	388,896
Advances from customers	3,213,052
Lease liability, current portion	338,744	327,944
Total current liabilities	6,697,920	1,300,220
Lease liability, net of current portion	1,104,611	1,291,570
Total Liabilities	7,802,531	2,591,790
Commitments and contingencies (Notes 1 and 6)
Shareholders' Equity:
Preferred stock, Series A 5% convertible, $0.08 par value, 571,429 shares authorized, none issued and outstanding as of February 28, 2022 and May 31, 2021
Preferred stock, undesignated, no par value, 4,428,571 shares authorized, none issued and outstanding as of February 28, 2022 and May 31, 2021
Common stock, $0.08 par value, 25,000,000 shares authorized, 12,851,924 and 12,307,157 issued and outstanding at February 28, 2022 and May 31, 2021, respectively	1,028,152	984,571
Additional paid-in-capital	42,108,865	38,836,743
Accumulated other comprehensive loss	(60,857)	(47,956)
Accumulated deficit	(33,318,358)	(30,546,335)
Total Shareholders' Equity	9,757,802	9,227,023
Total Liabilities and Shareholders' Equity	17,560,333	11,818,813
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, none issued and outstanding as of February 28, 2022 and May 31, 2021
Preferred stock, undesignated, no par value, 4,428,571 shares authorized, none issued and outstanding as of February 28, 2022 and May 31, 2021