jr east e231 series
The E231 series (E231系, E231-kei) is an electric multiple unit (EMU) train type used for commuter and outer-suburban services operated by East Japan Railway Company (JR East) in Japan
The type evolved from the earlier 209 series and E217 series EMUs, and the prototype train built in 1998 for trials on the Chūō–Sōbu Line was actually classified 209-950 series, later becoming E231-900 series. Full-production E231-0 series trains were subsequently introduced on the Chūō–Sōbu Line (10-car sets) and Jōban Line (10+5-car sets). Other variants include the 11-car E231-500 series for the Yamanote Line, and the E231-800 series with 2,800 mm (9 ft 2 in) wide bodies and end doors for use on Tokyo Metro Tozai Line inter-running services.
