They all passed to the London and North Eastern Railway at the 1923 grouping and received the classification F3.

They were a tank engine version of the T26 class 2-4-0s, albeit with a 3-inch (76 mm) shorter coupled wheelbase.

They were intended for use on long-distance stopping services,[1] and so they were all initially fitted with Westinghouse air brake equipment.

The R33 and D53 batches had been fitted with condensing equipment from new, but the LNER gradually removed them from all but one locomotive, the exception being an early retirement.

Thirty-seven locomotives lasted long enough to be renumbered in the 1946 scheme; fifteen of them became the property of British Railways in 1948, but only three of them lasted long enough to receive their BR number.