The Rab Cirrus Hut Slipper is now built with recycled PrimaLoftA(R) Silver Insulation Luxe and a recycled PertexA(R) Quantum outer. These slippers are ultralightweight, cozy and better for the planet. After a full day in climbing shoes or mountaineering boots your feet will thank you for slipping on these cozy slippers. Tough 600D nylon edge for abrasion resistance Non-slip PU outsole with EVA padded sole unit for comfort Rear pull-on loop Outer Fabric - Recycled 30D PertexA(R) Quantum with fluorocarbon-free DWR (50gsm) Lining - Recycled, soft 20D fabric PrimaLoftA(R) Silver Insulation LuxeA(TM) 100% post-consumer recycled synthetic insulation