llapsible Heel With Elastic Side Panels For Easy On/Off Oso Fleece Collar Lining For Added Comfort Sole Unit: Outsole Made With Up To 20% Recycled Rubber Thermoball™ Eco 100% Recycled Polyester Insulation Helps Keep Feet Warm Even When Wet Upper: Upper Made With 100% Recycled P.E.T. Ripstop With A Non-PFC Durable Water-Repellent (Non-PFC DWR) Finish For Added Water Repellency Your feet work hard, so they deserve the warmth and comfort of the Women’s ThermoBall™ Traction Mules V. These shoes combine ThermoBall™ Eco insulation with high-traction rubber outsoles to make slip-ons that are ideal for base camp, après ski, or shuffling out to grab the morning paper.