2S-007-032 N Gauge Pannier 3738 GWR Black lettered GWRPannier Tanks were used almost exclusively in Britain by the GWR. They were brought into service to replace earlier built and designed saddle tank locomotives. Their design offered the locomotive a low centre of gravity, reasonable range and easier access to the working of the locomotive. In all 863 were built between 1929 and 1950 and sixteen survive into preservation. Eleven 5700 saddle tanks were bought by London Transport for use on shunting