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SIGNIFICANT ACCOUNTING POLICIES (Details) - Inventories - USD ($)
Nov. 30, 2021
May 31, 2021
Inventories [Abstract]    
Raw materials $ 1,416,000 $ 1,583,000
Work in progress 708,000 1,006,000
Finished products 858,000 617,000
Total $ 2,982,201 $ 3,206,255