Muck Boots Arctic Sport High Performance Sport Boot - Men's Black 13. These Winter Shoes & Boots from Muck Boots have fleece lining and a 2mm thermal foam underlay added to the instep for added warmth. Muck Boots High Performance Arctic Sport Boots fit your calves snugly for warmth and have spandura layered over neoprene to protect against daily wear. Muck Boots Arctic Sport High Performance Waterproof Mens Boots also feature midsoles of molded EVA and rugged outsoles of molded MS-1 for safety and balance. Specifications for Muck Boots Arctic Sport High Performance Sport Boot - Men's: Manufacturer: Muck Boots Gender: Male Age Group: Adults Men's Shoe Width: Medium Boot Style: Winter Boot Color: Black Footwear Type: Winter Boots Activity: Winter/Snow Fabric/Material: Rubber Footwear Upper Fabric/Material: Rubber Insole Material: Neoprene Water Resistance Level: Waterproof Condition: New Lining Material: Premium Fleece Neoprene Insulation: Fleece Outsole Material: MS-1 Midsole Material: EVA Temperature Rating: -40 F / -40 C Features of Muck Boots Arctic Sport High Performance Sport Boot - Men's 100percent Waterproof Fully lined with 5mm neoprene for flexibility Fleece lining for warmth 2mm Thermal foam under the footbed for extra warmth Lightweight EVA midsole for added comfort Rugged outsole with grip Pull-tab for easy on and off Package Contents: Muck Boots Arctic Sport High Performance Sport Boot - Mens Muck Boots ASP-000A-BL-130: Arctic Sport High Performance Sport Boot - Men's Black 13