Please use mobile power. At the same time, our products do not include mobile power
1：Battery not included
2：We are Asian size, 2-3 sizes smaller than European size, please choose the right size according to our size chart。
3：Recommend batteries model, please use batteries with high USB Power Delivery（unit：W）， The higher the USB Power Delivery, the higher the heating temperature.（output Power (W)=Voltage (V) × Current (A).）
for example ：output power 10W=5V*2A / output power 22.5W=5V*4.5A
Zone 9 heating
This model is an upgraded version. The heating effect is the best. It can reach the whole body heating state. There are original heating elements on the front and back. At the same time, the power consumption is also very fast. It can also produce effects at extremely low temperatures.
Zone 2 heating
This version is the most economical. Only the backpack and the neck are heated. It contains two heating elements. The energy consumption is the lowest. The heating time is the longest.