The British-controlled São Paulo Railway procured ten Consolidation freight locomotives in 1909, designed by chief engineer Charles H. Fox and manufactured by the North British Locomotive Company in Glasgow. The tracks, which were very good by South American standards, allowed a heavy locomotive with an axle load of 16 and a half long tons.
Thus, the generously dimensioned boiler with Belpaire firebox immediately catches the eye. A Schmidt-type superheater was used, which was not standard on British locomotives at the time. Likewise, the valve gear was reversed by steam pressure and there were special bypass valves between the cylinders, which reduced the back pressure when taxiing with the regulator closed.