This part of ISO 5692 specifies the requirements for the attachment of agricultural non-balanced trailers and implements by means of hitch rings to the rear of the towing vehicle equipped with either a hook as specified in ISO 6489-1, or a piton-type coupling as specified in ISO 6489-4. Its purpose is to ensure the interchangeability of mechanical connections on agricultural towed vehicles.
This part of ISO 5692 is applicable to rings whose coupling point is below the centre-line of the rear axle and below the power take-off (PTO) of the tractor.
NOTE Other International Standards are under development for rings coupled above the PTO.