SNCF Class BB 27300 the number carried on the locomotive is prefixed with the number 8, to denote the unit as belonging to the Île-de-France division of SNCF. The first locomotives entered service in 2006 on suburban trains from Paris Montparnasse railway station. Current deployment sees a total of 25 locomotives operating services from Paris-Montparnasse on trains to Dreux, Mantes-la-Jolie and Rambouillet. At Montparnasse they have displaced older SNCF Class BB 8500 and BB 25500 locomotives. A further 42 locomotives operate from Paris Saint-Lazare railway station on trains to Poissy, Mantes-la-Jolie, Pontoise, Gisors, and Ermont Eaubonne. At Saint-Lazare BB 8500 and BB 17000 locomotives
SNCF Class BB 15000 with the BB7200 and BB22200 series and have even a great deal in common with cabs of other SNCF locomotives of the 1960s. This class was also the first to introduce the VI ("Vitesse Imposée") cruise control system which is now standard on all SNCF locomotives delivered after 1971. The electrical part consists of a single pantograph (type AM18U) which collects 25 kV from the catenary. Power is passed through a transformer which lowers the tension to about 1500 V AC and a bridge rectifier controlled by thyristors rectify it into DC, which is then fed into the traction motors.