These environmentally-friendly socks are made with a special polyester yarn which is spun from recycled plastic water bottles. They are specifically engineered for extreme moisture management. Our DRYALLDAY socks have a faster drying time, superior comfort, and exceptional softness. They have an all terry inside for unrivaled cushioning. Special ribbing up leg ensures socks will stay put. Designed by a podiatrist with comfort and foot health his main concern. Care instructions- Machine wash in cool water, tumble dry low.