The Road Vehicles Lighting Regulations 1989 determines the lighting requirements for all road vehicles, and the regulations for trailers vary depend on the size and the age of the trailer, but the minimum requirement is two red sidelights, two red stoplights and two red reflective triangles fitted to the rear. A number plate must be fitted and illuminated, and it must have amber indicators which have a flash rate between 60 and 120 times per minute, as well as visible or audible confirmation in the car that these indicators are working.