Mens Fruit of the Loom Invisible Sock Liners (4 Pair) 98% polyester/ 2% spandex Imported Machine wash cold with like colors. Use only non-chlorine bleach when needed. Tumble dry medium. Mens invisible sock liners. Set of four pairs. Includes two pairs of black and two pairs of gray. Extra wide gripper on back of heel to keep sock in place. Breathable mesh for ventilation. Moisture management helps keep feet drier. Perfect for lower profile footwear.