Coupling aid Pinpoint

Pinpoint consists of two glass fibre rods which are simply attached to the ball head of the AHK and the trailer coupling by means of a magnetic base. The ends of the glass fibre rods are now visible in the rear window. When reversing, cover the two rods and drive until the rod on the AHK is touched by the trailer and tilted - that's it.
Measure the height of the AHK.
Adjust the height of the trailer accordingly.
Install Pinpoint.
Shuffle so that both bars are congruent.
Cautiously reverse until the trailer overturns the red bar.