Battery Pack Special for Heated Vests20000mAh 5V2Alarge capacity, compatible with most heated devices (heated jackets, heating vests, and pants) on the market, and suitable for charging smart phones. Plug in for Automatic Starting up It was specially designed for heated clothing. When you wear heated clothing, it is inconvenient to replace the battery. With our products, you do not need to press the switch button because it will be power on as soon as the battery was connected. It will sleep automatically when it is not working. Multiple safety protectionOur power bank has a built-in intelligent safety protection chip of voltage regulator. Multiple protection procedures protect your devices against overvoltage, excessive current, overcharging, and short circuit. Balanced operating temperature, safe and not hot. 20000mAh Large CapacityWith a higher conversion rate, it can continuously heat vests for 6-15 hours (6 hours high temperature, 9 hours medium hours, and 15 hours lo