Section 20(3) in Rules Of The Road Regulations, 1989
(3)When a motor vehicle is being towed by another motor vehicle, the clear distance between the rear of the front vehicle and the front of the rear vehicle shall at no time exceed five metres. The tow ropes, or chains shall be of a type easily distinguishable by other road users and there shall be clearly displayed on the rear of the vehicle being towed in black letters not less than seventy-five millimetres high and on a white background the words "ON TOW".
