Get hitched the first time every time without assistance. End the annoying hassles of getting in and out of your vehicle to check alignment. The brightly colored balls are easy to line up using line of sight. When the balls touch, youre ready to hitch. Attach one of the units to the trailer and the other to the hitch magnetic bases stick firmly to any steel surface. Ideal solution for alilgning RVs utility trailers boat trailers and more!