These Fox River snow socks are lightweight and feature primaloft and merino wool for a warm and dry fit. They have an anatomical fit, meaning they are designed and knit to fit the left or right foot. (Don't worry, they're labeled L and R!) The heel and shin are cushioned for comfort and the spandex compression arch keeps the socks in place. Fox River socks are guaranteed against manufacturing defects for 1 year and are proudly made in America. Specs: 41% nylon, 32% PrimaLoft acrylic, 22% merino wool, 3% polyester, 2% spandex