Sorel Youth Size 4 Black Winter Unisex Yoot PAC Nylon Waterproof Boots NY1879 NY1879-010 PROTECTIVE OUTSOLE Handcrafted waterproof vulcanized rubber shell with Sorel aero-trac non-loading outsole. STAY WARM Removable 9 mm washable recycled felt inner boot with Sherpa pile snow cuff. SNOW-DAY FAVE The boot they need for a winter well-spent, this pair is waterproof, warm, and made to play. While they're tossing snowballs and braving frigid temps, its seam-sealed construction and Sherpa cuff will keep their feet cozy. A vulcanized rubber shell with an extra-grip sole provides traction on even the slickest terrain.