Thorlos Experia Thin Padded Running Ankle Sock Fiber Content: 66% THORWICK COOL polyester, 18% polyester, 15% nylon, 1% elastic Made in US Care Instructions: For longest product life and maximum comfort, wash and dry inside out (to fluff up the padding) using liquid fabric softener after each use (to condition the fibers for longer life) Running sock with Lycra mesh frame and cushion padding at heel and ball of foot Padding Level: Sculpted Thin Cushion Ribbed knit cuff