Airhole Size Chart
Measuring:
Head size: Measure around the fullest part of the head
Nose to mouth: Measure from the middle of the bridge of the nose to middle of the mouth
| Sizing | S/M | M/L | O/S |
| Head Size | 50 - 55 cm | 55 - 60 cm | N/A |
| 20 - 22 in | 22 - 24 in | N/A | |
| Nose to Mouth | 5.5 cm | 6 cm | 5 cm |
| 2.2 in | 2.4 in | 2 in |