What color must the center high mount stop lamp be?

The center high mount stop lamp, commonly known as the third brake light, must be red in color. This requirement is largely based on safety regulations that pertain to vehicle visibility during braking. A red light clearly communicates to drivers behind the vehicle that it is slowing down or coming to a stop, thereby enhancing overall road safety.

The use of red aligns with standard traffic signal colors for stop signals, helping to reduce confusion for drivers approaching from the rear. This consistency in color across various vehicle lights aids in quick recognition and response. Having the lamp in any other color, such as clear, amber, or white, would not provide the same immediate understanding of the vehicle's intent to stop, which is essential for preventing rear-end collisions.