Winter Heating Socks Rechargeable Electric Heated Socks Battery Powered Cold Weather Cotton Socks with 3 Level Temperature Setting for Men Women Outdoor Riding Camping Hiking Fishing Skiing A carbon fiber heating sheet at the bottom of foot heats your socks when you turn on the power, 35-55°C controllable temperature, can keep your feet warm during ice fishing, hiking, skiing and working outdoors in winter for about 4-5 hours after 3.5 hours full charged. Features: Made of thick cotton, soft and breathable with proper elasticity. Built-in a carbon fiber heating sheet, heating from the sole quickly and evenly. 35°C, 45°C, 55°C three level adjustable temperature and easy switch control. Come with a pair of 2200mAh rechargeable batteries, and they can fit in the 2 pockets on the tube of the socks. Can keep your feet warm for about 4-5 hours after about 3.5 hours full charged. One Size fits all. Long tube cotton socks can cover the calf, widely matched, warm and stylish. Best companion for cold indoor & outdoor activities like lounging, ice fishing, camping, snowboarding and working. Note: The temperature of socks without battery are constant, approx.50°C. Just connect the socks to your power bank with the transferred wire provided. Specifications: Material: Cotton Color: Black with battery / Grey with battery / Black without battery / Grey without battery (optional) Suggested feet size(CN): 35-44 Battery: 2x3.7V/2200mAh Li-ion battery  Charging time: 3.5h Duration: 4-5h Product Weight: 99.2 g / 3.5 oz Package Size: 16 * 8 * 8 cm / 6.3 * 3.1 * 3.1 in Package weight: 280 g / 9.9 oz Package List: 1 * Pair of Socks 2 * Rechargeable Batteries Notes: Washing by hand. Do not charge when unattended. Lithium battery exposure will be ineffective in an environment of minus 30 degrees. It is strictly forbidden e lithium batteries for moisture, water, fire and high temperature. Do not strike the lithium battery.