AXT (adventure cross training) styles are made for strenuous outdoor activities. They have an intimate blend of merino wool and premium polypropylene that dries 25% faster than other merino wool socks and is 3 1/2 times more abrasion resistant. The styles are light weight but dense and resist deterioration from mildew, perspiration and weather.Light weight, crew heightCushioned sole with mesh knit side channels for air flow to move moistureDimensional knit for a memory fitReinforced special areas for durabilitySpandex arch brace for support and snug fitSmooth.