Size Charts for Triple 8 Helmets
Adult
| US Size | Inches |
| X-Small | 20 1/10 - 20 1/2 |
| Small | 20 3/5 - 21 1/3 |
| Medium | 21 2/5 - 22 |
| Large | 22 1/10 - 22 9/10 |
| X-Large | 23 - 24 |
| US Size | Inches |
| X-Small | 20 1/10 - 20 1/2 |
| Small | 20 3/5 - 21 1/3 |
| Medium | 21 2/5 - 22 |
| Large | 22 1/10 - 22 9/10 |
| X-Large | 23 - 24 |