Webb had built 282 freight locomotives of the 0-8-0 wheel arrangement. All except the first one were compounds, which were of two types: there were 111 with two high-pressure cylinders outside the frames and a single low-pressure cylinder between the frames, which were known as Class A from 1911; and there were 170 with two outside high-pressure cylinders and two inside low-pressure cylinders, which were later known as Class B. Production ended in August 1904, over a year after Whale had succeeded Webb.