Ideal sock for high-output activities. Premier moisture wicking sock. Features ultra-light construction with an UltraSpun polyester body and Merino wool heel & toe. Includes ventilation panels, arch compression, a cushioned heel & toe, and a seamless toe to prevent chafing. 41% UltraSpun polyester, 39% nylon, 18% Merino wool, 2% Lycra spandex.