It will be the first bullet train dedicated to freight transport since the Tokaido Shinkansen Line started operations in 1964. The company plans to develop a dedicated freight-only Shinkansen that will feature larger doors to allow for smoother loading and unloading operations. The retrofit E3 series is being introduced because it takes time to design an entirely new train. The E3 series currently runs as the Tsubasa on the Yamagata Shinkansen Line, which links Tokyo with Shinjo, Yamagata Prefecture.