High Quality Content by WIKIPEDIA articles! The British Rail Class 450 third-rail DC EMU began service during 2003. They are a part of the Siemens Desiro modular train family and are more commonly known as the `Blue Desiro`. In standing with requirements of all new rolling stock for the South East region, provision has been made for future conversion to 25 kV AC overhead supply or dual voltage although, at present, no trains have been fitted with a pantograph. Used for outer suburban services, the Class 450 was built with standard and first class accommodation. The unit has a maximum speed of 100 mph (161 km/h).