The Muck Rugged II Winter Boot will protect your child's feet in severe cold with new 5mm CR Flex Foam insulation backed with a fleece lining. The lining adds extra insulation to keep cold out for kids that want to stay outside playing in the snow all day. The Rugged provides classic Muck comfort and warmth in an exceptionally durable and slip resistant package, and are easy to slip on and off. Insulation: 5mm of Neoprene with Fleece Lining Upper: Extended Rubber Exterior MidSole: EVA footbed for Muck Boot Comfort Outsole: Aggressive, durable, and slip resistant Height: 10 Avg. weight: 2.5 lbs.