ASTM PRO II PLUS SKULL HELMET SIZE CHART
| Head size (cm) | Helmet size | Skull cap size |
|---|---|---|
| 49 | 6 | 000 |
| 50 | 6 1/8 | 000 1/2 |
| 51 | 6 1/4 | 00 |
| 52 | 6 3/8 | 00 1/2 |
| 53 | 6 1/2 | 0 |
| 54 | 6 5/8 | 0 1/2 |
| 55 | 6 3/4 | 1 |
| 56 | 6 7/8 | 1 1/2 |
| 57 | 7 | 2 |
| 58 | 7 1/8 | 2 1/2 |
| 59 | 7 1/4 | 3 |
| 60 | 7 3/8 | 3 1/2 |
| 61 | 7 1/2 | 4 |
| 62 | 7 5/8 | 4 1/2 |
| 63 | 7 3/4 | 5 |
| 64 | 7 7/8 | 5 1/2 |
| 65 | 8 | 6 |