Easy to install, easy to retro-fit, used by OE manufacturers. No confusion with the respective towball sizes, fits 50mm and 1 7/8th easily, without the need to swap the handle.
The new Trailcom duofit coupling negates the need for the operator to change over the handle. The coupling simply automatically fits to the size of the towball.
Below is the measurement between the bolt hole center?s. The bolt holes are to suit 10mm bolts. Fitment should be by way of 4x high tensile bolts. NZs most commonly used coupling.