Hot rox electronic hand warmer and usb lead this handy version can be charged from any 5v usb charger so from a laptop pc a usb car charger or a traditional mains usb charger with adaptor bought seperatley hot rox comes with 2 heat settings providing up to 6 hours of heat on the medium setting and up to 3 hours of heat on the high setting it retains its charge for weeks on end so it is ready when you need it it can be reused up to 500 times smal pocket and hand size rechargable han