The British Rail Class 411 (or 4 Cep) electrical multiple units were built at Eastleigh works from 1956-63 for the newly electrified main lines in Kent. These units were based on the earlier Southern Railway 4 Cor design, built in 1937. Variants of the class 411 design included the class 410 and class 412 4 Bep units, which contained a buffet car in place of a standard trailer.