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Vehicle Requirements

You must use a combination of a Category B vehicle and a trailer which does not fall within Category B.

The Category B test vehicle must be either (A): at least 4.25 metres long, or (B): a 4-wheel vehicle.

The trailer must have a gross vehicle weight of at least 1,400kg, but must not exceed 3,500kg, and must have an L plate displayed on the front of the towing vehicle and the rear of the trailer. It must have a sound structure and the breaking and lighting systems must be in correct working order. The registration plate must match the vehicle combination.

The cargo compartment of the trailer must consist of a permanent, closed-box body at least 2.4m long. It must be at least as wide and high as the motor vehicle. It is acceptable for the closed-box body to be slightly less wide than the motor vehicle, however, as long as the view to the rear is only possible by use of the external rear view mirrors of the motor vehicle.

The real total mass of the trailer (its actual weight including its load) must be at least 800kg.
To achieve this, you must load your trailer with solid concrete blocks. For example, if the unladen weight of your trailer is 250kg, you will need about 30 solid concrete blocks (100mm x 220mm x 450mm), each weighing at least 19-20kg. 

(30 solid concrete blocks x 19kg each) + 250kg unladen trailer weight = 820kg

The concrete blocks must be evenly distributed throughout the trailer to avoid overloading the trailer's individual wheels/axles or towing hitch. It is recommended that the nose weight be 7% of the trailer's laden weight to comply with manufacturer and legal guidlines and provide optimal safety and stability.