Product Material: cotton cloth and carbon fiberSize: (flexible) sole length, 20 cm; sock length: 23 cm; sock opening: 9 cmBattery voltage: 3.7 VBattery capacity: 22004500 mAhTemperature control: 3 levels adjustableTemperature: low-end, 35 degrees Celsius; mid-range, 45 degrees Celsius; high-end, 55 degrees CelsiusColor: gray, blackQuantity: 1 pairPackage content: 1 pair heating socks (with battery charger)1. Battery Operation and Enlarge the Heating Elements To give your feet a more balanced warmth, our heated socks feature Enlarge the heating elements of the toes soles of the feet. keep your feet warm all day when they are fully charged. PS: The display of the adapter lights up red during the charging process green when fully charged.2. 3 adjustable temperatures Electric foot warmer with 3-stage temperature, the heating range of the electric socks is between 35 C 55 C. The red LED corresponds to the high temperature setting, the orange LED corresponds to the medium temperature setting the green LED corresponds to the low temperature setting.3. Flame retardant safety cotton The heated warm socks are made of cotton, polyester, spex. The breathable, quick-drying, specially developed, flame-retardant cotton makes you feel more secure during use. It is more important that the far infrared heating elements of the winter socks can stimulate the blood circulation. They are an ideal gift for people with arthritic feet cold joints.4. Washable an average size The heated sock battery support h wash machine wash. Note: Please remember to put the charging cable in the socks first before washing. heated socks unisex with average size. One size that fits everyone, super elastic stretchy for adults, men women.5. Widely Used and Best Gift Electric socks are perfect for a variety of indoor or outdoor events such as hunting, hiking, horse riding, fishing, biking, driving, running, camping, skiing, climbing, sleeping, etc. The Ski heated socks could also be an ideal gift for parents, friends, family members the elderly.