Class 120 Swindon 3-car DMUs

Introduced: 1958
Coupling code: Blue Square
Underframe: 64ft 6in
Engines: AEC 150hp
Transmission: Mechanical

Totalling 194 cars, three batches of these Cross-Country sets were built: 49 sets in 1958 for the Western Region; 7 sets in 1959 for the Scottish Region (best known for the Aberdeen to Inverness line although they also worked in other areas in the early years); and further 9 sets in 1961 for the Western Region.

In the late 1960s 22 sets were transferred from the WR to Derby to replace Cravens and BRC&W units. In 1977 seven sets were transferred from Cardiff to Chester in exchange for Gloucester build Cross-Country sets, followed by a further four by 1980. All the Chester sets (ex-Central Wales 2-cars) and some at Derby had their trailers replaced by Met-Camm trailers, although other types were also used.

Some cars had a trial refurbishment but this was found to be too expensive, meaning an early withdrawal for most of the class. The final vehicles survived until 1989, only one vehicle (a buffet car) was preserved.