Note 10 - Product Warranty - Changes in Product Warranty Liability (Details) - USD ($) |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
May 31, 2026 |
May 31, 2025 |
May 31, 2026 |
May 31, 2025 |
|
| Balance, beginning | $ 230,905 | $ 190,831 | $ 225,000 | $ 225,186 |
| Provision charged to expense | 99,541 | 98,336 | 177,480 | 183,376 |
| Less amounts charged-off | (152,785) | (75,238) | (224,819) | (194,633) |
| Balance, ending | $ 177,661 | $ 213,929 | $ 177,661 | $ 213,929 |