What must every bus or truck manufactured after model year 1959 be equipped with on the rear?

Every bus or truck manufactured after model year 1959 is required to be equipped with two stoplights on the rear. This requirement is based on safety regulations aimed at improving visibility for drivers following the vehicle, thereby reducing the risk of rear-end collisions. The addition of two stoplights ensures that drivers can more clearly see when the vehicle is stopping, providing vital information for safe driving conditions.

The use of two stoplights has become standard for vehicles to enhance safety, as a single stoplight may not provide sufficient warning in various driving situations. This regulation helps ensure that vehicles communicate their stopping actions effectively to other road users. It reflects an important aspect of automotive safety standards established to protect both drivers and pedestrians.