The Mountain Horse Ice High Rider III Tall Boot has a slim sole and shaped elegant design to provide warmth without the bulk. Now featuring Extensia foot part, which has been tested to withstand one million flexes in 14F weather. Heat-insulating Thermolite lining will keep feet and legs warm while waterproof construction keeps feet dry up to the start of the zipper. Sturdy and durable YKK zipper for easy entry and exit. Built in steel shank for increased stability.