The gross vehicle weight of a trailer pulled by a lorry of gross vehicle weight rating over 3.5 tons must not exceed:

According to the Road Traffic Act, the mass ratio of the towing vehicle and the trailer is strictly regulated for safety reasons. In the case of a vehicle combination with a heavy goods vehicle with a maximum authorised mass exceeding 3.5 t, the law permits the actual total mass of the trailer to be greater than the actual total mass of the towing vehicle, but by no more than 40%. This is to ensure the stability and braking effectiveness of such a heavy vehicle combination.