Over 2000 of the class were built between 1950 and 1970.

The class was built in two groups, each consisting of three ships.

The type was rare, with only two of these four classes built in quantity.

The class was built in 1880 and entered service in 1881.

The entire class was designed and built in Mexico.

It was the 7th ship of the class built at Komsomolsk.

The class was built for lightly used lines, replacing first generation single coach units.

The 17 class 406 sets were built by the same consortium as the class 403.

The Endurance class was built with a heavy emphasis on automation.

Only two classes of the 2-6-6-6 type were built.