It is a high-powered, light-weight vehicle with high acceleration for short- and medium-distance services with frequent stops.

The aluminium superstructure was built as flat as possible, both to minimize drag and to ease automated cleaning.

The acceleration is achieved by distributing traction motors among eight of the train's ten axles.

A Class 425 unit consists of four cars that share three jacobs bogies and can only be separated at maintenance facilities.

Different consists usually occur when the remains of partially destroyed units are combined to form one intact EMU.