The Class 120, were a cross-country DMU in three-car formation, built at the British Rail Swindon Works.
Totalling 194 cars, three batches were built:
1958 – 49 sets for the Western Region
1959 – 7 sets for the Scottish Region
1961 – a further 9 sets for the Western Region
The first batch was ordered for the WR’s West Country dieselisation scheme, which it hoped to complete by the end of 1959. The sets were expected to work between Bristol & South Devon. Their general reliability and good braking characteristics made them popular with drivers.
In February 1959, the BTC placed an order with BUT for the equipment for the seven ScR sets. These 120s were to work mainly on the Aberdeen to Inverness line although appearances at Oban were not unknown.
Otherwise the cars worked mainly in the Western and Midland Regions. Some cars had a trial refurbishment but this was found to be too expensive, meaning an early withdrawal for most of the class. Some of the London Midland Region’s units were transferred to Scotland in the mid-1980s, mainly finding use on local services from Edinburgh (notably to North Berwick). The final vehicles survived until 1989.