What color must rear reflectors be?

Rear reflectors must be red because this color is universally recognized as a warning signal to other drivers that a vehicle is present. Red reflectors enhance visibility at night and during low-light conditions, helping to prevent accidents by indicating the rear of a vehicle. The use of red for rear reflectors is consistent with traffic safety standards, which prioritize clear communication between vehicles on the road to ensure safety for all road users.

Conversely, yellow is typically used for side markers or as an indication of caution, clear reflects light without providing a warning signal, and green is not used for any vehicle reflectors as it does not convey the necessary alertness or caution needed for vehicles positioned from behind. Thus, red is the appropriate color mandated for rear reflectors to maximize visibility and safety on the road.