Lamps to show width of vehicle

The obligatory front lamps on all motor vehicles which exceed 6' 3" in width shall either be so placed that no part of the vehicle or its load or equipment, except the driving mirror or any direction indicator when in use, extends more than 12" beyond the centre of the lamp on the side at which the lamp is placed; or in the case of motor vehicles when either of the obligatory front lamps is not so placed, two additional lamps shall be fitted at the front of the said vehicle one on each side so that its centre shall not exceed the aforesaid distance of 12" and so as clearly to indicate the width of the vehicle to approaching traffic. The said additional lamps shall be focused below the horizontal and shall exhibit a white light of sufficient power only to indicate the width of the vehicle.