It led to the construction of a whole EMU in 1975, the ETR 401, built in two units by FIAT. One was put into public service on 2 July 1976 on the Rome-Ancona (later extended to Rimini) line, operated by Italian State Railways. Between Roma and Ancona (km. 295) the train took 2 hours and 50 minutes while the ordinary trains took 3 hours and 30 minutes. The train had four cars and was mostly considered a travelling laboratory for the new technology. The second unit was adapted for service to the broad gauge RENFE Spanish lines.