3. REVENUE (Details 2) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Net sales	$ 2,012	$ 5,533
Products and Services Transferred at a Point in Time
Net sales	1,570	4,859
Services Transferred Over Time
Net sales	$ 442	$ 674

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details