The 4-6-0 variant of the Standard class 4 was a mixed-traffic locomotive intended for lines where the Standard class 5 and the Black Five were too heavy. It was essentially a tender version of the Standard class 4 2-6-4T tank, but had a longer boiler barrel. Like the tank version, it had drivers with a diameter of five feet and eight inches and cylinders of 18 by 28 inches. Some were fitted with a double chimney. Their route availability of 4 ensured service on virtually all lines in Britain.

80 were built at Swindon, of which 45 were assigned to the Midland Region, 20 to the Western Region and 15 to the Southern Region. Most got BR2 or BR2A type tenders which held 3,500 imperial gallons of water and 6 tons of coal. Only the Southern region coupled their locomotives to BR1B tenders with 4,725 gallons and 7 tonnes, what worsened their road availability to 7. After their withdrawal between 1964 and 1968, six were preserved. Five of these are either operational or have run in preservation.