The British Rail Mark 4 is a class of passenger coaches built between 1989 and 1992 by Metro-Cammell at Washwood Heath for use on the East Coast Main Line, primarily in InterCity 225 sets operating between London King's Cross, Leeds, and Edinburgh. A total of 314 coaches were produced, designed to operate with Class 91 electric locomotives and Driving Van Trailers (DVTs) in fixed formations. The Mark 4 was a significant evolution from the Mark 3, incorporating automatic plug-type doors, fully sealed gangways, and controlled emission toilets (CET),
