The Class 379 is a is variant of the proven Electrostar product platform manufactured by Bombardier. Electrostars have operated extensively and successfully in the UK since first introduced in 2002, achieving some of the highest reliability figures in the UK. These 25kV electric trains are in a 4-car configuration and are operated by Abellio East Anglia Limited on the Stansted Express service between Stansted Airport and London. The trains are PRM compliant and have an enhanced passenger environment in first and standard class with passenger information, CCTV, excellent provision for luggage, passenger Wi-Fi and a wayside communication system that enables automatic updating of journey information and the first class seat reservations.