[1] As of November 2023,[update] a total of 20 ten-car trainsets have been built by Kawasaki Heavy Industries in Kobe from 2016, with the first trains entering service on 25 March 2017.

[2] The new 40000 series trains were built by Kawasaki Heavy Industries in Kobe from January 2016, with deliveries scheduled to continue from fiscal 2016 to 2019.

[2] Due to the use of fixed longitudinal seating throughout, the 40050 subseries EMUs are slightly lighter and accommodate more passengers than the 40000 series trains.

[7] The trains' interiors use LED lighting, and pairs of LCD passenger information screens are provided both above the doorways and suspended form the ceilings.

[2] A "Partner zone" area is provided at the end of car 10 with perch seats and space for wheelchairs and large luggage.

[1] The first trainset, 40101, was delivered from the Kawasaki Heavy Industries factory in Kobe to Seibu's Kotesashi Depot in September 2016.