Gel Therapy Socks are designed with a soft gel lining that comfortably conforms to your feet while gradually releasing medical grade mineral oil to moisturize and lubricate dry, cracked,callused skin. Gel Therapy Socks are made from bamboo charcoal. Hypoallergenic and latex free. This product is washable and reusable. Fits up to Size 13 US Mens Shoe Size.