This is one of a limited edition of just 25 pieces, uniquely and exquisitely weathered by Adrian Butler at "DIRTY BOY!" weathering for the Gaugemaster Collection.
This classic C.B. Collett design for the Great Western Railway was a development of the '51XX' general purpose 'Large Prairie'.
The boiler pressure was increased to 225Ib sq/ft giving the locomotives the extra power and better acceleration needed to work intensive Thames Valley suburban services from London Paddington towards Reading and Oxford.
This class of 70 examples proved to be ideally suited for this work and remained dominant until the arrival of BR suburban DMUs in the late-1950s and early-1960s.