Wigwam Women's Ironman Thunder Pro Low-Cut Running Sock (3-Pack) 50% Polyester, 23% stretch Nylon, 19% Acrylic, 7% Lyocell, 1% Spandex Made in US Machine Wash Lightweight cushioned sole running and fitness socks using the patented Ultimax moisture and odor control system for enhanced performance Features no-slip heel tab and foot hugging fit Y heel pocket and stretch provide a contoured fit Lifetime Guarantee