The SNCF Class Z 6400 electric multiple unit trains were built by Alsthom/Carel et Fouché from 1976 to 1979.

They were chiefly used in commuter service to the Gare Saint-Lazare in Paris, serving the northwest Paris suburbs.

Seventy-five of these 4-car units were built for use on suburban service in the west of Paris, operating mainly on the Transilien Line L. The 4-car units were most often used in double-formation as 8-car sets.

[1][2] They were progressively replaced by the Class Z 50000 units with the last commercial service of the Z 6400 running on 4 November 2020.

This was earlier than originally scheduled due to a downturn in passengers numbers during the COVID19 pandemic.