4. Costs and Estimated Earnings on Uncompleted Contracts (Details) - USD ($) |
12 Months Ended | |
|---|---|---|
May 31, 2026 |
May 31, 2025 |
|
| Details | ||
| Revenues Recognized For amounts included in billings in excess of costs and estimated earnings | $ 4,206,000 | $ 5,601,000 |