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. Forever Grey FEGY | Style No. 50160 Medium: Womens 7-9.5; Mens 6-8.5 Large: Womens 10-12.5; Mens 9-11.5 XLarge: Mens 12-14.5