 Holcroft's previous employment as an engineer involved with the GWR's 4300 class meant that the N1 used the same Churchward features as the N class to aid standardisation and the manufacture of parts.These included the use of long-travel valves for free running at speed, right-hand drive in the cab and driving wheels.The retention of the 2-6-0 wheel arrangement meant ample accommodation for the N class' tapered boiler with Belpaire firebox.