MUK LUKS has produced Polyester Fleece-Lined socks to cure icicle feet this winter! Our MUK LUKS Fleece Lined 2-Pair Knee High Sock Packs have a 95% Polyester 5% Spandex material and are lined with Polyester, Fleece. These socks are incredibly Warm, Comfortable on your feet and legs and can be worn casual or for a dressier outfit.