thorlos Lite Running Thin Padded Crew Socks 70% Acrylic, 27% Nylon, 3% Other Fibers Made in US No Closure closure Machine Wash Impact Protection- Thin light-weight padding in the ball and heel protects weight-bearing areas of the foot Constructed with thor-wick fibers for superior moisture-wicking for drier and cooler feet Made in Statesville, North Carolina, USA 30 Day Guarantee: Thorlos feel better than ordinary socks. If you do not agree, send the socks and your receipt to Thorlos for a full refund.