A portable jump starter (jump box, battery booster, jump pack, car jumper) is a powerful battery pack specifically designed to boost a vehicle’s discharged battery without the help of another car or power source. Power is drawn directly from the jump starter and transferred to the discharged battery using a set of portable jump starter-specific booster cables. These multi function devices also serve as battery packs and come equipped with usb ports, flashlight, portable air compressor and more. Compare All Portable Jump Starters