Thorlos Men's/Women's Thick Cushion Tennis Low Cut Socks Thorlon acrylic fibers are soft and resilient for comfort, blister protection and durability, while keeping feet cool and dry.. Thick cushioning in the ball of foot and heel provides maximum shock absorption. Extended cushioning over the toes protects feet during fast stops and starts. 87% Thorlon acrylic, 12% nylon, 1% spandex. Made in USA. Care: Machine wash inside out in lukewarm water. Tumble dry low. Fabric softener recommended.