Batteries Can be used with any mobile power supply with an output of 5V / 2A Safety Built-in thermal protection module. Once overheated, it stops until the heat returns to the standard temperature. Therapeutic benefits Helps to improve circulation and relieve pain from rheumatism and muscle strains. Ideal for people who have difficulty battling the cold in winter. Where to use Ideal for outdoor enthusiasts snowmobiling, motorcycling, camping, hiking, skiing, skating or just walking around in the cold season. How to use Press and hold the switch for 3-5 seconds, light up and select the desired temperature. *Unisex outdoor electric heated jacket *Composition: 100% polyamide, lining: 100% polyester *Heating pad: graphite fibre *Heating pad: 4 pads - 1 on the back + 1 on the neck + 2 on the front *Size: S M L XL XXL 3 XL 4 XL (please note: we stock Asian sizes, all European and American customers must add two sizes) *3-position temperature control, temperature range: 25-45C *Heating Heating time: all mobile power supplies with an output of 5V / 2A are available, if you choose the 8000MA battery, the heating time is 3-8 hours, the higher the battery capacity, the longer the heating time