This document specifies dimensions of ball-bearing turntable when mounted on a vehicle which is part of vehicle combinations specified in of ISO 18868:2013, Clause？4, to ensure their interchangeability.

This document also applies to the following:

—？drawbar trailers using a ball-bearing turntable to steer the front axle;

—？ball-bearing turntables assembled with the fifth-wheel of the road tractor (truck) to improve steering manoeuvre.