This SAE Recommended Practice provides test procedures, requirements, and guidelines for high-mounted stop lamps intended for use on vehicles 2032 mm or more in overall width. This document applies to trucks, motor coaches, van type trailers, and other vehicles with permanent structure greater than 2.8 m high. This document does not apply to school buses, truck tractors, pole trailers, flat-bed trailers, and trailer converter dollies. The purpose of the high-mounted stop lamp or lamps is to provide a signal over intervening vehicles to the driver of following vehicles
