79% Repreve(R) Recycled Polyester/17% Polyester/3% Elastane/1% Nylon. Built with Force(R) technology to wick sweat and dry fast. FastDry(R) wicks away sweat. Stain Breaker(R) technology releases stains. Fights odor. Repreve(R) recycled yarns. Heel, arch and toe cushioning. Arch support. Ribbed channels improve ventilation on leg. Mesh instep for breathability. Raised rib pattern on arch for enhanced moisture management. Abrasion-resistant yarns in toe. Stretch top stays put and reduces tension. Can also be worn as a liner.