Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Nov. 30, 2025	Nov. 30, 2024	Nov. 30, 2025	Nov. 30, 2024
Income Statement [Abstract]
Net sales	$ 1,210,000	$ 1,636,000	$ 2,590,000	$ 3,444,000
Cost of sales	(1,159,000)	(1,199,000)	(2,113,000)	(2,720,000)
Gross profit	51,000	437,000	477,000	724,000
Operating expenses:
Selling, general and administrative	1,231,000	1,173,000	2,561,000	2,533,000
Research and development	193,000	257,000	405,000	554,000
Total operating expenses	1,424,000	1,430,000	2,966,000	3,087,000
Loss from operations	(1,373,000)	(993,000)	(2,489,000)	(2,363,000)
Other income:
Dividend, interest, and other income	58,000	40,000	1,180,000	97,000
Total other income	58,000	40,000	1,180,000	97,000
Loss before income taxes	(1,315,000)	(953,000)	(1,309,000)	(2,266,000)
Provision for income taxes	(5,000)	3,000	(9,000)
Net loss	$ (1,320,000)	$ (950,000)	$ (1,318,000)	$ (2,266,000)
Basic net loss per common share	$ (0.45)	$ (0.06)	$ (0.48)	$ (0.13)
Diluted net loss per common share	$ (0.45)	$ (0.06)	$ (0.48)	$ (0.13)
Weighted average number of common and common equivalent shares:
Basic	2,908,164	2,140,179	2,774,167	2,121,340
Diluted	2,908,164	2,140,179	2,774,167	2,121,340
Other comprehensive income (loss), net of tax:
Foreign currency translation	$ (1,000)	$ (4,000)	$ 2,000	$ (10,000)
Comprehensive loss	$ (1,321,000)	$ (954,000)	$ (1,316,000)	$ (2,276,000)