Joseph Tomlinson developed a goods locomotive with the wheel arrangement 0-6-0 and double frames for the Taff Vale. A total of 44 were built by Taff Vale's own workshops in Cardiff and by several other manufacturers.
Rebuilt to 0-4-4T
Locomotive Magazine, December 1910
Under Tom Hurry Riches, four of these locomotives were rebuilt to passenger tank locomotives with the wheel arrangement 0-4-4T. This conversion resulted from the elimination of the third driving axle, the installation of coal and water tanks and the addition of a trailing bogie.