State-of-the-art engineering for your feet by Mother Nature EH comfort cuff Anti-bunching ankle support Snug fitting heel pocket Y heel stability fit Foot fatigue relief Antifriction toe seam Advanced flex motion sides Ultra bamboo has extreme moisture wicking power 76% Bamboo rayon, 18% Polyester, 3% Nylon, 3% Spandex Elite PRO-X700 Ultra Bamboo Senior Knee-Length Socks, Medium, Black MS1158487 MS1158487 698548105853