PREMIUM PROTECTION: A fully formed ABS outer shell with high quality EPS foam ensures safety on impact, so you can confidently carve the mountain on your skis or snowboard. BREATHABLE DESIGN: This ski helmet has 9 vents for ultimate temperature regulation, and our glove-friendly BreezeBar allows you to customize the airflow in your helmet whenever you need to. ADJUSTABLE FIT: Helmet sizing is adjustable with an ErgoKnob dial that allows you to ?quickly dial in the most comfortable, snug fit for your head. REMOVABLE WASHABLE EARMUFFS: After things get sweaty on the slopes, you can easily remove and wash your helmet’s earmuffs (Hand wash only), or leave them out for a breezier descent. SIZING: To determine the correct ski helmet size, wrap a measuring tape around your head. The tape should rest just above your ears and remain level around the circumference of your head. S: 52-55.5 cm, M: 55.5-59 cm, L: 59-62 cm