Featuring the most advanced Vibram outsole technology to date, Muck Arctic Ice Series Extreme Conditions Mid-Height Rubber Women's Winter Boots are specifically engineered to deliver grip and performance on wet ice. The Arctic Grip Outsole pods offer the most advanced traction in wet ice environments, and the multi-direction lug design provides sure footing on multi-surface terrain. The outsole of these women's winter boots also features the Vibram Icetrek full base layer for unparalleled traction on dry ice. From a comfort perspective, the women's last is specially designed to match the contours of the female foot. The 5 mm CR Flex-Foam is flexible, 100% waterproof, and possesses excellent heat-retention properties. It combines with the fleece lining to ensure superior warmth with a comfort rating of -40 F to 40 F (-40 C to 4 C). Tough Spandura and an extended rubber shaft round out the cold weather coverage of these waterproof winter boots.