The North Eastern Railway (NER) Bogie Tank Passenger (BTP) locomotives were designed by Edward Fletcher in 1873.

[1] With the introduction of the NER Class O (LNER G5), BTP locomotives started to become redundant.

Many class BTPs gained a further lease of life in the early 1900s by being converted to work the Steam Autocars (push–pull trains) then being introduced.

The driver also had full (Westinghouse) brake control via a second air pipe connection to the engine.

This high pressure air supply also worked a whistle mounted above the driving compartment.