Designed for versatility, you can take this helmet rock or ice climbing, mountaineering, cave diving, and even canyoneering. It features an expanded polystyrene liner to prevent helmet jostling, integrated ventilation shutters for colder conditions, and a lightweight design for an enjoyable climbing experience. . . . ABS shell meets all standard climbing certifications. . Polystyrene foam. . Sliding ventilation shutters. . Sidelock headband adjustment. . Headlamp compatible. .