BS ISO 3584:2020 pdf free.Road vehicles-Clevis couplings-Interchangeability. BS ISO 3584 1 Scope This document specifies the characteristics necessary for the mounting and interchangeability of clevis couplings on the frame (cross member, drawbeam or mounting bracket) of towing vehicles for trailers. This document is applicable to clevis couplings intended for connection to trailers equipped with a drawbar eye on the drawbar...