[2] Before through-running operations began on 9 October 1986, the trains were required to satisfy fire resistance regulations due to the long tunnel on the Aizu Kinugawa Line.

[2] Trains are painted in "jasmine white" with "sunny coral orange" and "purple ruby" lining.

[3] Passenger accommodation consists of fixed 4-seat bays with a seat pitch of 1,525 mm (60.0 in).

[2] With the popularity of the new trains, an additional eight new 2-car sets were built, including one set for the Yagan Railway, enabling all "Rapid" services between Asakusa and Shimo-Imaichi to be increased to 6-car formations from the 9 August 1988 timetable revision.

[2] A further two newly built sets were added to the Yagan Railway fleet coinciding with the start of Aizu Kinugawa Line services.