[1] The design limited the maximum axle load to 16.3 tonnes.

[2] Bogie shrouds and diaphragms between cars were fitted to this set as a noise reduction measure, but these features were not used on the 200 series design due to the complications this added to maintenance.

The latter were used on production 200 series trains with increased seat pitch.

After this, the train was used for test running on the Jōetsu Shinkansen prior to the opening of the line.

[2] From January 1983, the train was converted to become the 7-car Class 925-10 "Doctor Yellow" track and overhead line inspection train S2 with the insertion of track condition recording car 921-41 built by Tokyu Car Corporation in November 1980.