7. INCOME TAXES (Details 3) - USD ($) $ in Thousands	May 31, 2021	May 31, 2020
Deferred tax assets:
Net operating losses	$ 15,584	$ 13,634
Lease liability	372	483
Credit carryforwards	5,298	5,089
Inventory reserves	1,006	1,005
Reserves and accruals	890	739
Other	450	319
Gross deferred tax assets	23,600	21,269
Deferred tax liabilities:
Operating lease right-of-use assets	(342)	(449)
Less: Valuation allowance	(23,258)	(20,820)
Net deferred tax assets (liabilities)	$ 0	$ 0