Designed to wear UNDER your normal socks and gloves. They're made of an incredibly lightweight aluminized fabric developed by NASA to warm astronauts, by reflecting body heat. Lightweight, stretchable. Sock liners and knee highs; 60% nylon, 40% metallic. Glove liner; 65% polyester, 25% metallic, 10% nylon (100% cotton cuff). Pairs.