Fly Helmet Sizing Chart
| ADULT HELMETS | ||
| SIZE | HAT SIZES | INCHES |
| X-SMALL | 6 5/8 - 6 3/4 | 20 7/8 - 21 1/4 |
| SMALL | 6 7/8 - 7 | 21 1/5 - 22 |
| MEDIUM | 7 1/8 - 7 1/4 | 22 3/8 - 22 3/4 |
| LARGE | 7 3/8 - 7 1/2 | 23 1/8 - 23 1/2 |
| X-LARGE | 7 5/8 - 7 3/4 | 24 - 24 3/8 |
| 2X-LARGE | 8 or greater | 25 1/8 - 25 1/2 |
| YOUTH HELMETS | ||
| SIZE | INCHES | |
| YOUTH SMALL | Under 20 1/2 | |
| YOUTH MEDIUM | 20 1/2 | |
| YOUTH LARGE | 20 7/8 | |