Heated socks for everyone: These unisex foot warmers are made of cotton, and they are moisture-absorbing, quick-drying, breathable, and soft. They are elastic and fit everyone (adult size). Perfect for outdoor activities: The heated sock is perfect for a variety of sports and outdoor activities such as climbing, motorcycling, walking, skiing, snowboarding, and hunting. Adjustable temperature: The electrically heated socks have a 3-stage temperature setting, high, medium, and low. They heat up quickly and your feet will soon be wonderfully warm. Long battery life: The socks are heat-insulating and keep your feet warm for a long time. The thermal socks are heated by rechargeable batteries that provide a heating time of 4-8 hours. These battery-heated socks with two rechargeable batteries will keep you warm all day! Specifications: Size: One size Sock length: 30-40 cm Foot sole length: 19-30 cm Material: Cotton, carbon fiber Voltage: 5 V Battery voltage: 3.7 V Heating temperature: 35-55 ℃ Temperature adjustment with 3 temperature modes: 55/45/35 ℃ Working time: 4-8 hours Charging time: 4 hours Battery capacity: 4000 mAh cylindrical lithium battery 18650 Data cable specification: 35135 Package includes: 1 pair of heated socks with rechargeable batteries