The Sm6 is a class of high-speed tilting electric multiple unit trainsets built by Alstom.

A total of four trainsets were originally built for the now-defunct Allegro train service operated by Karelian Trains, a joint venture between Russian Railways (RZhD) and VR Group (Finnish Railways).

VR has announced that they have seized full control of the trains and would begin using them in domestic services in 2025.

[5] The Sm6 fleet is primarily maintained at Ilmala depot north of Helsinki, although some maintenance mainly related to Russian technical systems was also performed in Saint Petersburg.

The units were equipped for both the Finnish and Russian railway technical systems, which differed substantially.