First Choice for Ski Helmet: The impeccable fit of both the Kelvin II ski helmet and OutdoorMaster ski goggles ensures a seamless experience. Perfectly designed for winter enthusiasts, this helmet is a must-have for those who crave the thrill of skiing, skating, snowboarding, and more | Premium Protection: Keep your head covered in this snow helmet as you carve the mountain on your skis or snowboard. Fully formed ABS outer shell with high quality EPS foam to ensure safety on impact | Breathable Design: The Kelvin II ski helmet's 14 air vent holes work harmoniously to ensure effective ventilation, Purposefully designed ventilation apertures shield you from freezing winds | Adjustable Fit: The snowboard helmet's detachable lining, earmuffs, and soft chin band offer cozy warmth. The adjustable dial to perfectly customize your fit.Lightweight and user-friendly, it relieve head pressure, ensuring an enjoyable snowy adventure | Sizing: To determine the correct 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. Small: 18.89-21.25 inch(48-54 cm), Medium: 21.25-22.83 inch(54-58 cm), Large: 22.83-24.41 inch(58-62 cm)