The Re 450 is a push-pull electric locomotive passenger coach type which is used by Swiss Federal Railways on S-Bahn services in Zürich. They are also known as DPZ, short for double-decker push-pull train, and is the first double decker train type operated by SBB-CFF-FFS, following successful trials of a French VO 2N bilevel train borrowed from SNCF in the early-1980s. Under the old Swiss class system, they would have been known as Re 4/4V. They are only found working with formations of three double-deck passenger carriages, the rear-most of which has a driving cab to allow push-pull working. At peak times trainsets may be coupled together to form a train consisting of three locomotives and nine passenger vehicles. Most S-Bahn lines use this stock and it is the most common on the network. All Re 450 coaches received a mid-life refurbishment at the SBB-CFF-FFS workshops at Yverdon-les-Bains between 2011 and 2018.