Class 491 (4-TC)
(later became class 438)

 Although included here in the EMU section these 4-TC units were in fact unpowered trailer units intended for use with the very powerful  4-REP units. Typically a 4-REP and two 4-TC units would be used to make up a twelve car train as pictured here. The train would run in this formation from Waterloo to Bournemouth where the REP would be removed and a class 33/1 loco would take one (or  in some cases both) of the TCs on over the (then) non-electrified section to Weymouth. The 4-TC units could be used with a class 33/1 diesel or class 73 ED loco with the loco on either end of the train.
 In the late eighties the class was re-classified as class 438 and renumbered from 401-434 to 8001-8034.

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