Made of thick cotton material, breathable and well-filled, thick, soft and elastic.Three gears, intelligent temperature control, three-level temperature adjustable, convenient to carry and wear when going out.It ensures that your feet are warm and comfortable. It is the perfect solution for arthritic feet and long-term cold feet and joint stiffness.It has sufficient power and lasting battery life. The rechargeable lithium battery is fully charged and can be used for 5-8 hours.No fear of washing, remove the battery, and use waterproof treatment for the power interface.Unisex, comfortable to wear, don’t let your feet catch cold. It is a detachable heating sock, easy to carry, warm and healthy.Product name: electric heating socksProduct material: cottonTemperature range: 40~60°CCapacity: 4000mAhSize: 79*45*1 5mmWeight: 175g (one pair)Input: 5V/2AOutput: DC 3. 7VIt can be washed by hand. When washing, remember to put the charging plug in your pocket and remember to remove the battery.Package List:1 x Pair of Socks2 x Battery Box1 x ManualNote:It can be washed by hand. When washing, remember to put the charging plug in your pocket and remember to take out the battery.Please allow 1‑3cm error due to manual measurement. Thanks for your understanding.Suitable for outdoor sports.