What color are side marker lamps required to be towards the rear?

Side marker lamps that are located towards the rear of a vehicle are required to be red. This color designation is established by regulations designed to enhance visibility and communication among vehicles on the road. The use of red for rear marker lamps serves to alert other drivers to the presence and boundaries of a vehicle, particularly in low visibility conditions, such as during dusk or at night.

In contrast, other colors have specific uses; for example, white is utilized for front side marker lamps and for other functions like headlights. Amber is typically reserved for signaling or indicating caution, such as on turning signals, rather than for rearward visibility. Clear lights, while also used in certain contexts, do not specifically correspond to the regulation for rear side marker lamps. Thus, red is definitively mandated for these markers to ensure clarity and safety on the road.