The Great Northern Railway (GNR) Class N2 is an 0-6-2T side tank steam locomotive designed by Nigel Gresley and introduced in 1920. Further batches were built by the London and North Eastern Railway from 1925. They had superheaters and piston valves driven by Stephenson valve gear.Some locomotives were fitted with condensing apparatus for working on the Metropolitan Railway Widened Lines between King's Cross and Moorgate.