The British Rail Class 319 is a dual-voltage electric multiple unit train capable of operating on 25 kV AC from overhead wires or 750 V DC from a third rail. They were built by BREL York for use on north-south cross-London services.Built in two batches in 1987–88 and 1990, the units were primarily used on the then-new Thameslink service operating from Bedford to Brighton and various other destinations south of London.