Waterproof USB Charging Heated Jacket. Any power bank with an output of 5V/2A can be used. Built-in thermal protection module. Once it is overheating, it would stop until the heat returns to the standard temperature. help promote blood circulation, relieving pains from rheumatism and muscle strain. Perfect for parents and families who have difficulty fighting the cold in winter.Perfect for outdoor enthusiasts snowmobiling, motorcycling, camping, Hiking, Skiing, Skating, or just plain walking around in cold seasons. with 10 area heaters.color: black/green.