Darn Tough's Colorado sock was designed to show the big mountains some big love. This perfectly light bomber is a simple go-to sock for skiers and riders who know less is more. Over-the-Calf height is ideal for skiing and riding in deep conditions while Ultra-Light Merino Wool provides legendary warmth without the bulk. And since Merino Wool is naturally antimicrobial this sock repels bacteria and odor. Still made in Vermont. Guaranteed for life.