Whether you're relaxing by the fireside or exploring your surroundings, freezing conditions are no match for the ThermoBall™ V Traction Winter Mules. SPECIFICATIONS - Upper, Recycled P.E.T. Ripstop with Non-PFC Durable Water-Repellent (Non-PFC DWR) Finish ; Sole Unit, Outsole Made with up to 20% Recycled Rubber ; Approx Weight, ½ Pair: 201 g / Pair: 402 g ; Sizes, Medium: 5-11 (Whole Sizes) FEATURES - UPPER: Recycled P.E.T. ripstop upper with non-PFC durable water-repellent (non-PFC DWR) finish to help keep feet dry ; Lightweight ThermoBall™ Eco insulation retains warmth, even when wet ; Oso fleece collar lining for comfort ; Collapsible heel with elastic side panels for easy on/off ; SOLE UNIT: Outsole made with up to 20% recycled rubber TECHNOLOGIES - Thermoball™ ecoMade from post-consumer recycled polyester, lightweight Thermoball™ Eco effectively insulates in cool, damp conditions.