[4] Starting in 2023, 500 series trains, nicknamed "Urara", were introduced in the greater Okayama and Fukuyama (Okayama/Bingo) areas.

[5] The first batch of trains, branded "Red Wing", have logos applied on the sides of the body and on the prominent anti-fall plates on the front ends, which inspired the name.

[6] Passenger saloons use LED lighting, and the trains are equipped with universal access toilets and wheelchair spaces.

The 227-0 series fleet consists of 276 vehicles (42 two-car sets and 64 three-car sets), which were delivered from autumn 2014 for test running and driver training before entering revenue service initially on the Sanyo Main Line between Shiraichi and Iwakuni, replacing ageing JNR-era 115 series EMUs.

[12] The 227 series fleet consists of 42 two-car and 64 three-car sets, allowing formations of up to eight cars to be formed in service.

Once the order is complete, the trains would have smart card readers on board, expanding ICOCA acceptance to all JR West service in Nara prefecture and on Wakayama Line.

[46] The sets carry a pink livery, which is associated with cherry blossoms as well as the softer climate experienced along the lines in which these trainsets will be running.