The British Rail Class 307 electric multiple units were built by BR at Eastleigh Works from 1954 to 1956. They were initially classified as AM7 before the introduction of TOPS.

Thirty-two of these 4-car units were built for services on the Great Eastern Main Line.  All units were formed of four cars. When originally built, units were numbered in the range 01s-32s and were composed of two outer driving trailers, an intermediate trailer composite (i.e. with some first-class seating) and an intermediate motor brake. The units were constructed to operate off the 1,500 V direct current (DC) overhead power system used on Eastern Region suburban lines from Liverpool Street to Shenfield and Southend Victoria. However, in the late 1950s / early 1960s, these lines were converted to the 6.25 kV/25 kV alternating current (AC) overhead system, which was adopted as standard and coincided with the introduction of new Class 302 (AM2) units. Therefore, from 1960 to 1962, the entire AM7 fleet was extensively rebuilt at Eastleigh Works to allow units to operate from the new voltage system. The work including moving the guard's compartment from the motor coach to one of the driving trailers. At the same time, units were renumbered into the range 101–132.

In the early 1990s, the British Rail parcels sector Rail Express Systems identified the need for driving trailers to operate in push-pull mode with a locomotive. This would remove the time-consuming process of changing the locomotive to other end of the train to allow it to leave a terminus. These new vehicles were called Propelling Control Vehicles (PCVs), since it was envisaged that they would only be used to propel a train into or out of a terminus, and not used at high speed or over long distances. It was decided to convert the vehicles from the many redundant Class 307 vehicles that were stored at various locations around the country.

One driving Brake trailer from unit 307123 has been saved for preservation. Two PCV conversion has also been saved for preservation.