Starting in the late fifties, British Railways ordered some types of electric multiple units whose body had the same structure as the Mark I coaches. What they have in common is that one or two cars of each set had four traction motors. In other aspects, they had differences depending on their area of service.

The first was the class 302 introduced in 1958 for operations in the London area. They were originally designated AM2 and consisted of four cars each with a huge number of slam doors. One of the inner cars had four traction motors with 143 kW each and was not only designed for operation under 25 kV, but also 6.25 kV for certain lines in London. The first sets of 112 were withdrawn in 1984 and the last ones in 1998.

The class 303 was similar and originally called AM3, but was built for operation in the Glasgow area and had only two doors on each side of each car. Each set consisted of three cars and had 155 kW per traction motor. After 92 sets of class 303, only 19 were built of the class 311 that was introduced in 1967. These were initially called AM11, could only operate under 25 kV, delivered 165 kW per motor and were manufactured by another company. While the small number of class 311 sets was already withdrawn by 1990, class 303 was only withdrawn by 2002.

The class 432 had greater changes compared to the others and was originally designated 4-REP by the Southern Region. Its class designation in the 400 range indicates hat it was designed for the third-rail DC network in the south and southeast of London. The concept consisted of a high powered four-car EMU that hauled additional three- or four-car trailer sets. So the class 432 had eight 300 kW traction motors in the two outer cars and enough power to haul the class 438 TC trailer set that also had driver compartments. In total, 15 powered sets and 34 trailer sets were built. These were withdrawn by 1991.