Highly cushioned for comfort and built for a long life, our Heavyweight Merino Wool-Blend Knee Socks are engineered for warmth in cold conditions. They're made with Responsible Wool Standard (RWS) wool certified by Control Union (TE-00052557). We blend RWS wool with nylon and spandex for excellent stretch and recovery that lasts the lifetime of the socks. The purchase of RWS-certified products demonstrates demand for better animal welfare practices and responsible land management in the wool supply chain. The Heavyweight Merino Wool-Blend Knee Socks is fully backed by our Ironclad Guarantee and you can find it on Patagonia.com. | Patagonia Heavyweight Merino Wool-Blend Knee Socks in Potters Red, Medium - Nylon/Spandex/Wool