The MU in question is called the Bombardier MR-90. The end doors are for low platforms only and are plug doors; the center doors are for high platforms only and are sliding doors. Here's 408 in the lead
on a train at Mont Royal. The MR-90 replaced these CN MUs
, and also heavyweight trailer cars hauled by these boxcabs from 1914
that were retired in 1995 (81-year service life, yes).
PS. Railpictures has a nasty habit of trying to send you spyware.