Thorlos Unisex Thick Padded Running Low Cut Sock 80% Thor-Lon Acrylic , 19% Stretch nylon , 1% Spandex Made in US Turn Inside Out-Machine Wash-Use Liquid Fabric Softner Padding Level: Maximum Cushion Key Benefit: Maximum Protection = Maximum Comfort Guarantee - Your feet will feel better or your money back! Proudly MADE in the USA | North Carolina Thorlos clinically-tested padding under the ball and heel provides maximum protection from friction, the primary cause of blisters, and impact protection where needed most Constructed with THORLON fibers for superior softness, resilience, durability, and moisture-wicking for drier, better feeling feet Cushioning over the toes to help protect against runner's toe (black toe) Flat knit instep and cushioning in arch for better fit, more support and less pressure on the feet for a more comfortable run