the king pin 36 of the present invention is compatibly configured to be encased within a mounting ball 50 prior to engaging the receiving feature 22 of the base 20 as such the mounting ball 50 provides a uniform spherical surface to the king pin 36 thereby simplifying the alignment and coupling of the pin box 30 and the base 20 the mounting ball 50 comprises an aluminum alloy or another suitable material for example in one embodiment the mounting ball comprises a non corrosive durable material the mounting ball 50 is generally spherical and further comprises a cavity 52 for receiving the king pin 36 additionally the mounting ball 50 may include any feature necessary to enable the mounting ball 50 to securely retain the king pin 36 for example in one embodiment the mounting ball 50 is secured to the king pin 36 via one or more fasteners such as bolts in another embodiment the mounting ball 50 is provided in two opposing halves in this embodiment the two halves are positioned around the king pin 36 and then affixed to one another via two or more fasteners alternatively the mounting cavity 52 of the mounting ball 50 may include a set of threads or other feature for mechanically attaching to the outer surface of the king pin 36 without the need of a.