FULTON #63300, SOLO HITCH ALIGNMENT KIT(Docking Aid).

SOLO Trailer Alignment Kit (extends from 13" to 42")

  Now you can be in the driver's seat when aligning your hitch to the trailer's coupler… literally. The magnetic trailer alignment kit comes with two chrome-plated telescoping rods that each magnetically attach to your vehicle’s hitch and the trailer's coupler. Once in place, just raise the bright yellow markers to a height where you can see both of them from the driver's seat, get in and drive. When the two markers are aligned, you're in position to hook them up!

ADDED BONUS!! 
   Ever had a hard time seing the end of the dock as you back into your slip at the marina? Your low down view obscured by the boats design?  Can't mount anything to the dock permanently due to the steel and concete or the marina does not allow it?

  This product makes that all go away!  Just extend the telescopic rod and attach to the dock** before you leave and you instantly have a 42" tall reference point when you return.

**If your dock is wood, simply attach a couple of large washers to the dock with screws to serve as the base for the SOLO's magnet.