10. Income Taxes: Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($)	May 31, 2024	May 31, 2023
Deferred tax assets
Allowance for doubtful receivables	$ 6,200	$ 6,200
Tax inventory adjustment	57,300	84,300
Allowance for obsolete inventory	188,100	273,200
Accrued vacation	163,000	136,600
Accrued commissions	0	9,800
Warranty reserve	100,700	62,700
R&D tax credit	0	0
R&D capitalization	1,479,800	678,500
Stock options issued for services	181,200	331,300
Deferred Tax Assets, Gross	2,176,300	1,582,600
Deferred tax liabilities
Excess tax depreciation	(1,163,685)	(1,013,985)
Net deferred tax assets	$ 1,012,615	$ 568,615