The fleet of fifty-seven Capitalstars is split into two subgroups,

twenty 378/1s that are DC (third rail) only with the remaining thirty-seven being classified as 378/2s being dual DC and AC (pantograph fitted). When they were introduced in 2007 as four-car sets it was already clear that this was not going to provide enough capacity so an additional one car per set was procured. These have been steadily added to the sets over the last few years with a few still to be modified. As can be seen, London Overground makes great play of the fact that they have undertaken this task! 378228 arrives at Kensington Olympia station with the 12.31 Clapham Junction to Willesden Junction service.