Trailer hitch

The arrangement has a coupling ball (7) for accommodating a traction eye with a ball cup and a retaining device (1) and a retaining bolt (5) reversibly connected to the retaining device. The retaining bolt has an internal hexagonal bore and at least one lubrication opening. The retaining device can be pivoted from a first position into a second position and fixed in the first position by at least one fixing element. An independent claim is also included for the following: (a) retention bolt for retaining device for a coupling arrangement has.