Please use a power bank with an output voltage of 5V, and our package does not include a power bank.Electric Heated Jacket with Hood: the jacket is made by cotton, polyester and waterproof materal, which can help keep warm and preventing water and rain.4 Heating Areas: The heating component of heated jacket is made of imported carbon fiber, and it has four heated areas, including the left abdomen, right abdomen and the back, back nape position.3 Heated Temperature Conttrol: Three temperatures can be selected just by only pressing a button on this warm jacket. High temperature: red color(60 C/140 F), Medium temperature: blue color(50 C/122 F), Low temperature: green color(40 C/104F ).Easy To Use: Connect the USB port of the jacket to the power bank, and then press and hold the switch on the chest for 2 seconds, the vest turns on the heating mode.