*1. 9 zone fever zone, neck, shoulders, back, waist, abdomen, stomach are fully warmed, and can withstand the severe cold -40 low temperature. *2. Double control switch, can separately adjust the heating area of the front and the back heating area, more personalized warmth and can extend the heating time. *3. The in-depth mechanism of the constant temperature of the far-infrared carbon fiber heating sheet helps to eliminate the dampness and cold in the body. *4. Fast heating and heat preservation in 3 seconds, no need to wait, heat release, long press for 3 seconds to open. *5. Heat quickly for 1 minute to eliminate the cold and keep warm. *6. With mobile power storage pocket, easy to travel. *7. Set the temperature you want to respond to a variety of environments. *8. A button to heating, three stall temperature control, intelligent heating. *9. Polyester fabric plus waterproof treatment. *10. Do not wring it dry by hand. *11. General USB interface power supply, longer service life,anti water splashing and washable. How to use: 1. Take out the USB plug. 2. Insert the mobile charger. 3. Turn on the mobile charger. 4. Press the chest temperature control switch for two seconds. 5. The red light flashes, means heating automatic. 6. After red light flashes for 5 minutes,then automatic turn to white light,means medium temperature. 7. Manual adjustment has three level,red light means hign-temperature heating continuously. White light means medium heating continuously,blue light means low heating continuously. 8. Press the chest temperature control switch for two seconds to extinguish and stop heating. Dear Friend: Our size table is based on Asian sizes, Asian sizes L = EU sizes M = American sizes S. Please choose the size according to the weight and height. According to our size table, this is correct. Please note that this project does not include mobile power supply. You should bring it yourself. Please use 5V mobile power supply. USB interface less than 20,000 mAh.