Section 39-21-19 - Signal lamps and signal devices1. Any motor vehicle may be equipped and when required under this chapter must be equipped with a stop lamp or lamps on the rear of the vehicle which shall display a red light visible from a distance of not less than three hundred feet [91.44 meters] to the rear in normal sunlight, and which shall be actuated upon application of the service (foot) brake, and which may, but need not, be incorporated with one or more other rear lamps.2. Any motor vehicle may be equipped and when required under this chapter must be equipped with lamps showing to the front and rear for the purpose of indicating an intention to turn either to the right or left. The lamps showing to the front must be located on the same level and as widely spaced laterally as practicable and when in use display a white or amber light, or any shade of color between white and amber, visible from a distance of not less than three hundred feet [91.44 meters] to the front in normal sunlight, and the lamps showing to the rear must be located at the same level and as widely spaced laterally as practicable and when in use display a red or amber light, or any shade of color between red and amber, visible from a distance of not less than three hundred feet [91.44 meters] to the rear in normal sunlight. Any motor vehicle or combination of vehicles eighty inches [20.32 decimeters] or more in overall width, and manufactured or assembled after January 1964, must be equipped with the lamps required by this subsection mounted and spaced in the same manner but visible from a distance of not less than five hundred feet [152.4 meters] to the front and rear in normal sunlight. When actuated the lamps must indicate the intended direction of turning by flashing the lights showing to the front and rear on the side toward which the turn is made. Turn signal lamps may, but need not, be incorporated in other lamps on the vehicle.3. No stop lamp or signal lamp may project a glaring light.