[7] The overall styling was overseen by Japanese industrial designer Ken Okuyama, and is intended to evoke images of the Namahage demons and kantō festival lanterns for which Akita Prefecture is famous.

[8] The main body colour is "Hiun" (飛雲) white with crimson roof and "arrow silver" bodyside stripe.

[7] The pre-series set, S12, was delivered to Sendai Depot in June 2010,[9] and formally accepted by JR East on 8 July.

[2] From 15 March 2014, the maximum speed was raised to 320 km/h (200 mph) on the Tohoku Shinkansen, with the maximum speed on the Akita Shinkansen tracks remaining at 130 km/h (80 mph), allowing journey times between Tokyo and Akita to be reduced by an average of 12 minutes.

[3] In May 2014, the E6 series was awarded the 2014 Laurel Prize, presented annually by the Japan Railfan Club.

[14] While the first sets from both Hitachi and Kawasaki Heavy Industries were delivered by sea to Sendai, set Z9 was delivered from the Kawasaki Heavy Industries factory in Kobe by rail to Akita Depot over three days from 31 May to 2 June 2013, mounted on temporary narrow-gauge (1,067 mm gauge) bogies and hauled by freight locomotives.