This article is about the single 1913 4-4-2T locomotive. For the older and larger-wheeled 'County Tank' 4-4-2T class, see GWR 2221 Class. For the 0-6-0PT pannier tank locomotives numbered 46xx after 1940, see GWR 5700 Class § Numbering and liveries.
It was designed as light suburban locomotive, based on the successful 4500 class 2-6-2T engines. Compared with these, it had larger (and fewer) coupled wheels, intended to allow higher speeds with local trains. The only example built spent most of its career in the Birmingham area, and was not considered a success. The limited adhesion and restricted tank capacity meant that it did not improve on the 4500 class, and the larger 2-6-2T classes handled the suburban traffic better. It was moved to western Wales in 1918 for use on the lines to Pembroke Dock and Neyland. It was withdrawn in 1925 and scrapped.[2][3][4]