[9] They were built by Niigata Transys and were delivered to JR East's Aomori Depot in September 2010,[10] entering service from 4 December 2010, coinciding with the opening of the Tōhoku Shinkansen extension to Shin-Aomori.

[3] In November 2022, JR East announced that the Resort Asunaro sets would be remodelled for two new sightseeing trains: Hinabi (ひなび) and Satono (さとの, stylized in all uppercase).

[12] JR East announced on 1 June 2023 that these sets would make their final trips in revenue service on 20 August of that year, ahead of their remodels.

[13] The four-car Resort Shirakami – Aoike train for use on the Gono Line was delivered from Tokyu Car's Yokohama factory to JR East's Akita Depot in September 2010.

[15] The train entered service on 16 July 2016,[16] replacing the earlier KiHa 48 four-car DMU trainset previously used.

[18] The four-car Kairi (海里) train was announced by JR East in October 2018, developed around the cuisine of Niigata and Shonai, as well as the scenery of the Sea of Japan.

Intended to operate between Niigata and Sakata stations on Fridays, Saturdays, and holidays,[19] the exterior features an orange-and-white colour scheme, inspired by sunset and snow.

[28] Car 1 carries a green livery inspired by the lush green mountains and rice fields in the Tohoku region while Car 2 carries a blue livery inspired by the pure water, clear air and deep sea.