The chest switch design has 9 heating control zones on the front and back, and the heating zone is designed for the cold-prone parts on the back of the neck.One-button heating, three-level temperature control intelligent heating, warm level45C, comfortable level35C, energy-saving level25C.Intelligent heating vest, using graphene fiber for heating, safe performance, soft and stable, reliable and comfortable.Long battery life, only 5V voltage, 10,000 mA of continuous heating for 6 hours. The energy-saving mode can be used for up to 12 hours.It can be washed for a long time as new, and the power interface is insulated and waterproof. Unplug the power supply, it can be machine washed and received, but it cannot be wrung out by hand.Optimizing down cotton, anti-drilling down technology, make you comfortable and warm throughout the winter.