Warm, lightweight, and glove friendly adjustments make the Rocket Winter Boot the kids' all-round winter favorite. Sledding, building a snow fort or just running around all day in the snow is what they're designed for. A lace-lock collar keeps the snow out. A removable 3-layer moisture wicking 8 mm Zylex? liner keeps their feet cozy and dry. Durable construction keeps you happy. Water Resistant. Rated for -40?.Water Resistant Waterproof 600 denier nylon upper to keep kids dry Removable 8mm Zylex liner Moisture wicking lining helps move sweat away from skin Adjustable snow collar with Kamik's easy grab lace lock Glove friendly adjustable midfoot velcro strap NiteRays reflective technology for added safety Waterproof, lightweight and flexible synthetic rubber shell Kamik's SNOWAVE synthetic rubber outsole Rated to -40F/-40C Avg. weight for pair: 1.68 lbs.