Muck Boots  Women's Rubber Boots Arctic Sport II Karo EU38 R1 Fabric Technology: Antibacterial, CR Flex-Foam, Moisture Control, NZYM Technology, Odor Control, Waterproof. Brand: Muck Boots. Upper: Synthetic fabric. To slip in. Insole: BioDeWix, Double Layer, EVA. Midsole: Lightweight, molded EVA. Outsole: With silicone nubs, durable. Heat resistance: -40°C. Lightweight, pull-on tab. Heel: Flat. Calf-high. Design: Logo, Check. Toe style: Round. Lining: fleece, neoprene, warm feel. Fit: Stretch.