The MR-90 was a class of single-level electric multiple unit (EMU) railcars built in 1994–1995 by Bombardier Transportation for the Société de Transport de la Communauté Urbaine de Montreal (STCUM) and last operated by Exo. They were ordered when the Deux-Montagnes line was completely rebuilt from 1993 to 1995 and all the equipment and infrastructure was replaced. With the closure of the Deux-Montagnes line on December 31, 2020, in favour of the Réseau express métropolitain project, the MR-90 fleet was withdrawn from service. They were subsequently transported to Exo's Pointe-Saint-Charles maintenance center for storage. A request for information has been issued to determine the fate of the cars. In 2022, exo announced that the MR-90 coaches would be scrapped. A single married pair, composed of motor car number 400 and trailer with cab number 485, was set aside for preservation at the Canadian Railway Museum in Saint-Constant.