 The route's narrow bridges and tunnels were unable to accommodate the class, and provided justification for using the narrower 3-cylinder N1 class 2-6-0 on the route.Despite these restrictions, the class was capable of hauling heavy loads at moderate speeds, a useful attribute that was exploited throughout the Second World War.The entire class came into British Railways' ownership in 1948 and could be seen in most areas of the Southern Region.