The Re 450 is a three-phase electric locomotive based on the Re 456 developed for private railways. It has only one driver's cab at one end and was specially developed for use with double-deck push-pull trains with control cars. Accordingly, they are only used with these sets in fast commuter transport. The locomotives and the control cars are equipped with an automatic coupler on the fronts so that several sets can be coupled together quickly during operation. They were modernized between 2011 and 2018, with parts of the traction electrics also being renewed. 