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. 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.