Section 39-21-17 - Spot lamps and auxiliary lamps1. Spot lamps. Any motor vehicle may be equipped with not to exceed two spot lamps and every lighted spot lamp must be so aimed and used so that no part of the high-intensity portion will strike the windshield, or any windows, mirror, or occupant of another vehicle in use.2. Fog lamps. Any motor vehicle may be equipped with not to exceed two fog lamps mounted on the front at a height not less than twelve inches [30.48 centimeters] nor more than thirty inches [76.2 centimeters] above the level surface upon which the vehicle stands and so aimed that when the vehicle is not loaded none of the high-intensity portion of the light to the left of the center of the vehicle shall at a distance of twenty-five feet [7.62 meters] ahead project higher than a level of four inches [10.76 centimeters] below the level of the center of the lamp from which it comes. Lighted fog lamps meeting the above requirements may be used with lower headlamp beams as specified in subsection 2 of section 39-21-20.3. Auxiliary passing lamps. Any motor vehicle may be equipped with not to exceed two auxiliary passing lamps mounted on the front at a height not less than twenty-four inches [60.96 centimeters] nor more than forty-two inches [106.68 centimeters] above the level surface upon which the vehicle stands. The provisions of section 39-21-20 apply to any combination of headlamps and auxiliary passing lamps.4. Auxiliary driving lamps. Any motor vehicle may be equipped with not to exceed two auxiliary driving lamps. Any auxiliary driving lamp mounted at a height of less than sixteen inches [40.64 centimeters] or more than forty-two inches [106.68 centimeters] above the level surface upon which the vehicle stands may not be lighted when the vehicle is used upon a highway. The provisions of section 39-21-20 apply to any combination of headlamps and auxiliary driving lamps.