They were designed and built by Sharp Stewart and were virtually identical to the Class A that preceded it, with the addition of a trailing bogie.

7 was vacuum fitted and thus was able to haul passenger services as the relief engine for No.

23 to 32) were delivered between December 1889 and February 1890 and differed from the first batch in having a Type 2 boiler.

[1] The locomotives passed to the Great Western Railway in 1922.

This article relating to steam locomotives operated in the United Kingdom is a stub.