|British Rail Class 201|
|Manufacturer||Eastleigh and Ashford Works|
|Maximum speed||75 mph (121 km/h)|
|Weight||55 long tons (56 t)|
|Prime mover(s)||English Electric 4-cylinder type 4SRKT Mark II|
|Power output||500 bhp (370 kW) at 850 rpm. Total 1,000 bhp per set.|
The British Rail Class 201 (or 6S) six-car diesel-electric multiple units (DEMUs) were built in 1957–1958 at Eastleigh railway works and Ashford railway works. They were built for use on the London to Hastings line. Several tunnels along the route had restricted clearance, meaning that these units were built with a narrow body profile.