Sorel Big Kids Caribou: Winter Boots  Youth Unisex Sizes Sorel's ICONIC Winter Boot The tough rubber sole provides extreme traction in the snowiest days.   MIDSOLE: 2.5 mm bonded felt frost plug. UPPER: Waterproof nubuck leather upper. Seam-sealed waterproof construction. INSULATION: Removable 9 mm washable recycled felt inner boot with Sherpa pile snow cuff. OUTSOLE: Handcrafted waterproof vulcanized rubber shell with Sorel aero-trac non-loading outsole. HEEL HEIGHT: 1 1/6 in. PLATFORM HEIGHT: 5/7 in. BOOT SHAFT HEIGHT: 7 1/3 in. BOOT SHAFT CIRCUMFRENCE: N/A Measurements based on size 1. Uses: Light Rain, Heavy Rain, Light Snow, Heavy Snow