[3] A larger boiler was implemented, and such confidence was placed in Drummond's design that an order of 50 locomotives was placed straight off the drawing board.

[3] Detail improvements on this final batch were a wider cab and revised wheel splasher that hid the 'throw' of the coupling rod, with cross-water tubes fitted into the firebox.

This batch was also fitted with the Drummond "watercart" eight-wheel tender for longer running, whilst the previous was retrofitted with the design.

[3] Their sterling performance as a class precluded any further modifications, apart from the removal of the cross-water tubes, an enlarged smokebox, addition of a stovepipe chimney, and an increase of the cylinder bore to 19 inches (480 mm).

[5] Under Southern Railway ownership from grouping in 1923, the locomotives were outshopped in Richard Maunsell's darker version of the LSWR Sage Green with yellow lettering on the tender, with black and white lining.

They proved of great use west of Salisbury where their light axle loadings and short frame lengths were better suited to the tight curves of the Southern's Western Section.

It was finally withdrawn from capital stock in July 1963 but continued to work special trains until October of that year.

Following lengthy periods in store at Fratton, Stratford, Preston Park, Tyseley and York, it was again overhauled in the early 1980s on the Mid Hants Railway and returned to steam in 1983.

It then moved to the Bodmin and Wenford Railway, and was returned to steam in August 2010 following a heavy overhaul, including repairs to the cylinder block at the Flour Mill Workshop in the Forest of Dean.

It was repainted in early British Railways lined black colour scheme and was regularly used on passenger trains at Bodmin.