The following description was taken from Transafe WA: A Guide to The Movement of Towed Agricultural Implements in Western Australia
A Handbook for Western Australian farmers, prepared and published by Department of Transport, Driver and Vehicle Services (March 2014).
This handbook is a guide to the safe towing of agricultural implements and an interpretation of the law. It is NOT the law, but a simplified version of the road rules contained in the Road Traffic Act 1974 and Regulations, currently in Western Australia. It is not intended to be used as a legal document. More information can be obtained online at www.transport.wa.gov.au/dvs