The British Rail Class 411 (4CEP) electric multiple units were built at Eastleigh works from 1956–63 for the newly electrified main lines in Kent.

The standard units contained passenger seating only, and formed the backbone of the new fleet.

Units were formed of two outer driving motors cars with 2nd class (later Standard Class) seating in open saloons, sandwiching two intermediate trailer cars – one a corridor second and the other a First/Second corridor composite.

The 4 BEP fleet were classified as Class 410 by British Rail under the new computer numbering system introduced in 1968.

The numbering of individual vehicles and details of when units were built are shown in the table below.

During the late 1970s and early 1980s, British Rail recognised that the 4 CEP fleet was in need of refurbishment.

Refurbishment included moving the guard's compartment from both the motor cars to one of the intermediate trailers.

Many of the 4BEP fleet were converted to standard units, since the requirement for buffet cars had declined.

Following evaluation, the contract for the refurbishment of the rest of the fleet was awarded to BR's Swindon Works.

At the same time, units were renumbered from their original sequence into the later BR standard system reflecting TOPS class and sub-class, though in Southern Region style, only the last four digits were carried - so for example 411 501 was abbreviated to 1501.

Subsequent refurbished standard units were renumbered in the range 1501–1621, and reclassified as Class 411/5.

The three former SR division; South-Eastern, South Central and South-Western; all operated 4 CEP units, and are dealt with separately here.

However, as the units were non-standard in the SC fleet, they were withdrawn and transferred to South West Trains.

The South Eastern (SE) division inherited the largest fleet of 4 CEP units.

These removed trailers had not had so much work carried out on them at the time of refurbishment (as they were basically unchanged apart from cosmetic appearance and installation of hopper windows) and many had become severely corroded.

1592, was repainted by staff at Ramsgate depot into its original Green livery, to commemorate the final months in traffic for these units.

1602, was the only 4 CEP unit repainted into Connex livery, after it received derailment damage outside London Bridge station, and had to be repaired at Eastleigh works.

Due to a unit shortage It was later reinstated in August 2005, and remained in traffic until late September.

These were gradually overhauled, and were employed on a range of duties, including services to Portsmouth, Reading, Southampton, Bournemouth and Weymouth.

The fleet stayed reasonably static until 2002, when SWT reformed several sets.

The displaced carriages were inserted into the 4 BEP units, which were renumbered 2311–2317 (reclassified as Class 412/1).

The standard units lasted until early 2004, when they were either withdrawn and scrapped, or transferred to South Eastern Trains.