Made with 75% Ultra-wicking M.D. Acrylic, 15% Nylon, and 10% Spandex for exceptional comfort and strength. All of our socks feature our "stretch-to-fit" sizing system and our exclusive "easy-fit" cuff for a perfect fit every time on any foot. These features create superior softness and comfort and help eliminate blisters and hot spots. We also feature a double stitched heel & toe for added strength and durability. We deliver superior quality and high-tech comfort in every SockGuy sock we make. We guarantee it.