Inventory (Details) - USD ($)	Aug. 31, 2021	May 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials	$ 595,406	$ 503,344
Work-in-process	4,771,180	5,076,377
Finished goods	201,147	355,875
Gross inventory	5,567,733	5,935,596
Less allowance for obsolescence	100,000	100,000
Net inventory	$ 5,467,733	$ 5,835,596

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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