The LSWR T3 class was a class of express passenger 4-4-0 steam locomotives designed for the London and South Western Railway by William Adams. Twenty were constructed between 1892–1893.
The class were numbered 557-576, and had been intended as a variant of the X2 class with slightly smaller driving wheels (6 ft 7 in versus 7 ft 1 in). In reality, the coupled wheelbase was lengthened by 6 inches and the locomotive was fitted with a firebox 6 feet 10 inches deep – the largest firebox of any of Adams' designs.
Thanks to PaulHobbs and Trainboi1 for their mesh library elements, many of which have been used in the model.