| Helmet HP1 | Junior | Small | Medium | Large |
| Inches | 20.4"-22" | 20.8"-22.4" | 21.2"-22.8" | 22.4"-24" |
| Centimeters | 52-56cm | 53-57cm | 54-58cm | 57-61cm |
| Helmet HP1 | Junior | Small | Medium | Large |
| Inches | 20.4"-22" | 20.8"-22.4" | 21.2"-22.8" | 22.4"-24" |
| Centimeters | 52-56cm | 53-57cm | 54-58cm | 57-61cm |