Advanced Material and Heating System This heated socks are made of 80% cotton, 10% polyester and 10% elastic material. Strong water absorption,strong air permeability. Wear soft, warm and comfortable. Heating system adopts titanium crystal sodium meter heating technology, can be washed, heating fast.^ Power Display,Advanced Chip for Three Temperature SettingThe foot warmer is powered by 7.4V 4000mAh high concentrated energy battery,The biggest defference is that it can display the amount of electricity on the switch.While using advanced chip for constant temperature control,to solve the problem of power reduction and large temperature drop when the voltage is low.^ Targeted Design According to Human Foot Type According to ergonomics, we focus the heat generated by the heating system on the cold toes, which is more energy-saving and more comfortable at the same time.The Heated Socks battery pockets we use 3D design, stockings battery pockets will be more elastic, so that you can stay away from the pressure of the battery.^ Free Size, Washable, A wide Range of Uses The heated socks are elastic and suitable for different foot types. For adults, men and women, ideal for hiking, hunting, ice fishing and other outdoor activities in cold weather.^