COMPRESSION SOCKS Socks deploy graduated compression?they squeeze more and more tightly the farther they are from the heart. These colorful compression socks can help reduce blood pooling in the legs and speed up the return of blood to the heart. Stimulating blood flow helps improve oxygen delivery to your muscles, which speeds up muscle recovery, helps prevent cramping, swelling, spider veins, and circulation issues common among diabetics. Material: Cotton, Polyester, Spandex (Made in China) S/M - Shoe 7-10.5 / Calf Size 9-15 inches L/XL - Shoe 8-12 / Calf Size 14-19 inches Designed to offer compression for enhanced blood flow circulation These therapeutic socks help soothe muscle pain Machine Wash With your purchase, the Sock Panda donates socks to someone in need. Thank you!