The British Rail Class 302 (pre-TOPS AM2) was a type of electric multiple unit (EMU) introduced between 1958 and 1960 for outer suburban passenger services on the London, Tilbury and Southend line. This class of multiple unit was constructed using the Mark 1 bodyshell and was slam-door. Overview Like all the Eastern Region AC EMUs of the period, they were equipped to operate on both 25 kV AC and the reduced 6.25 kV voltage in the inner London areas where headroom for the overhead wires was reduced. On the LT&S the changeover point was just east of Barking station on both Upminster and Tilbury routes with the link to Forest Gate being at 6.25kV ac. Each unit was formed of four coaches, in the following formation: DTSOL (Driving Trailer Second Open with Lavatory) – MBS (Motor Brake Second) – TCsoL (Trailer Composite semi-open with Lavatory) – DTS (Driving Trailer Second). The initial set numbers were 201–312, later prefixed by the class number 302 with the introduction of TOPS. The Battery Driving Trailer and Driving Trailer were fitted with drop head buckeye couplers with screw coupler in the Guards Van, retractable buffers are also fitted only on outer ends of the Battery Driving Trailer/Driving Trailer. Service history Public service started on 16 March 1959 with Class 302s working the first electric passenger trains between Colchester and Clacton at 25kV ac. A revised half hourly timetable started on April 13 from Colchester with a 8 car train splitting at Thorpe-le-Soken with half going to Walton-on-Naze Some Class 302s were used for crew training in Manchester before the Class 304 units were introduced in April 1960. They were among the first electric units delivered to the Eastern Region and, although ordered for the LT&S electrification, a route they were long associated with, they were used initially on the Liverpool Street to Hertford East, Bishop's Stortford and Enfield Town lines when they were electrified in November 1960. The 302s also stepped in when electrification was extended from Chelmsford to Colchester in 1961 and when the Class 305 units were having problems on the then new north-east London electric services. Some formations were temporarily reduced to three cars for the Enfield Town services. The first 25 units remained on the GE main line for the bulk of their lives, with the remainder operating on the LT&S from Fenchurch Street from 1962. Between November 1961 and