The CW-X Ventilator Compression Sock is made with a four-way stretch fabric that helps improve circulation. Anatomical toe design features a non-restricting toe box that allows for increased functionality and movement. Taping supports the calf muscle and ankle, gradual compression aids in circulation and recovery. Arch support stabilizes and supports the arch of the foot to help reduce fatigue. Mesh venting in key perspiration zones, moisture wicking. 60% polyester/11% cotton/10% acrylic/10% nylon/9% polyurethane. Imported. SIZING: M - Fits men's shoe size 6-8.5, women's shoe size 7-9.5. L - Fit's men's shoe size 9-11.5, women's shoe size 10-12.5. XL - Fits men's shoe size 12-15.