LMS Stanier Class 4P 3-Cylinder 2-6-4T is a class of steam locomotive designed for work over the London, Tilbury and Southend Railway route. All 37 were built in 1934 at Derby Works and were numbered 2500–2536. The third cylinder was provided to allow increased acceleration between the many stops on the L.T.&S.R. line. The inside cylinder and valve gear created additional maintenance and was deemed unnecessary for other duties. The locomotives were built in 1934 at LMS Derby Works.

The class were withdrawn from 1960 to 1962. The first member of the class to be built, No. 2500 is the sole survivor of this class and is painted in LMS lined black livery.