For comfortably warm feet, no more cold feet. Wool stands for warmth & this is in particular true for the wool fleece top layer made from Merino wool. The base layer of insulating wool felt protects against rising cold. The wool fleece top cover is light & retains heat. It warms your feet & provides pleasant thermal comfort. The anti-skid layer keeps the insole firmly in place inside the shoe. All layers are carefully stitched together by TENCEL lyocell tarns. This product is made from 100% natural & renewable fibres.