The trailer coupling can have a resting body (1) fitted on it to reduce wear on the traction eye. The resting body has a recess fitting round the lower guide bush (3) for the coupling bolts.. The recess in the resting body is reduced at least locally in diameter by a bulge (1b). The bulge acts like a press stud, gripping behind a raised portion (3a) of the lower guide bush. The resting body may be made entirely of plastic, with the bulge running all the way round, or may consist of an upper part of metal and a lower part of metal, with the bulge only in two opposite regions.
