The BB 25500 was a mixed-traffic locomotive for service under both AC and DC power systems in use in France. As a part of the BB Alstom family, it had many features in common with the original BB 16500. Most notably were the monomoteur bogies which had only one traction motor each and a gearbox that transmitted the power to both axles. This could be switched between a top speed of 90 and 140 km/h while stationary. 194 locomotives were built by Alstom between 1964 an 1976. From 25588, they had a longer body to increase cab space.
Their ride qualities at speed were not very good due to their short bogie wheelbase, what earned them the nickname “Danseuses” (“Dancers”). In 1999, locomotives of the class were assigned to Fret (freight), TER (regional) and Transilien (Paris commuter). The TER locomotives had push-pull control for operating trains with a driving trailer. Some also operated into Switzerland. Withdrawals commenced in 2006 and 13 were sold to Regiotrans, later Regio Călători of Romania where they operate as class 425. In France, the last ones were withdrawn in 2021 and five are being preserved.
