Northern Territory Consolidated Regulations Northern Territory Consolidated RegulationsIn testing a fifth wheel coupling built for a 75 millimetre kingpin used in a B-double or road train to decide whether its D-value complies with rule 161(1), the longitudinal movement (after readjusting the jaws of the coupling using a kingpin built to the dimensions mentioned in rule 165(3)(a)) must not be over 4 millimetres.