Made by the best in the business - Pro Feet. Reinforced Heel and Toe for Longer Wear.Fully Cushioned Foot for Shock Absorbency. Support Channels at Ankle and Instep to reduce fatigue and keep sock in place. Welt Top for Better Stay-Up Performance. 72% High Bulk Acrylic, 23% Streth Nylon, 5% Elastic (TK)