What this product can offer you is that this socks will be self-heating to use for outdoor and winter, it will keep warm and perfectly fit your foot which is comfortable and high elasticity. And it can effectively to massage your foot for releasing fatigue, swelling and dampness of legs. Comes with high quality soft cotton, it will be gentle to use with long lifespan, and the tourmaline design on bottom will warm and relax your foot for locking temperature. By making with cotton material, this sock is skin-friendly and comfortable to wear. The length of the product is 22cm, the width is 12cm. It is suitable for outdoor activities, skiing, snowboarding, hiking, hockey and other sports. Item Name: Heated Socks Material: Cotton Features: Self-Heating, Soft, Comfortable Suitable Size: 37-44 Size Details: 22cm x 12cm(Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 Pair of Heated Socks Safe Heated Socks Reduce Swelling