GEOGRAPHIC INFORMATION (Tables)

9 Months Ended

Feb. 28, 2021

Geographic Information Disclosure [Abstract]

Revenue from External Customers by Geographic Areas [Table Text Block]

	Nine Months Ended				Three Months Ended
	February 28, 2021		February 29, 2020		February 28, 2021		February 29, 2020
Revenues from sales to unaffiliated customers:
United States	$	374,000	$	389,000	$	133,000	$	165,000
Asia		1,653,000		1,863,000		756,000		404,000
Europe		3,781,000		1,226,000		2,611,000		509,000
South America		146,000		166,000		64,000		95,000
Middle East		190,000		313,000		65,000		4,000
Other		1,000		11,000		-		-
	$	6,145,000	$	3,968,000	$	3,629,000	$	1,177,000