The listing, Car battery charger/jump starter has ended.
This is a Car/Truck jump starter/battery charger that works by plugging the silver end into the car with the good battery's power port/cig lighter,, then the other end plugs into the car's power port/cig lighter that needs jump started or battery charged. This works although it does take a little longer to charge than the heavy duty jumper cables. The great thing about these is that you don't even have to open your hood or get out of your car/truck whatsoever. Great for cold weather or rainy days!