Inventory (Details) - USD ($)	Nov. 30, 2020	May 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials	$ 580,276	$ 658,024
Work-in-process	7,844,831	8,586,404
Finished goods	542,726	963,009
Gross inventory	8,967,833	10,207,437
Less allowance for obsolescence	100,000	100,000
Net inventory	$ 8,867,833	$ 10,107,437

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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