Muck Boot Kids Rugged II Hi Boot Black The new Kids Rugged II will protect your child's feet in severe cold with new 5 mm CR Flex-Foam insulation backed with a fleece lining. This lining adds extra insulation to keep the cold out for kids that want to stay outside in the snow all day. Many different bright colors. 5mm CR Flex-Foam Warm Fleece Lining Extended Rubber Exterior EVA Footbed Aggresive, Durable Outsole Durable Rubber Exterior Sizes: C7-13, Y1-7 Comfort Range: -40*F to 40*F Color: Black Size: 13