2-4-4

In Whyte notation, a 2-4-4 is a steam locomotive with two unpowered leading wheels followed by four powered driving wheels and four unpowered trailing wheels.

Other equivalent classifications are:

UIC classification: 1B2 (also known as German classification and Italian classification)

French classification: 122

Turkish classification: 25

Swiss classification: 2/5

The equivalent UIC classification is 1'B2' (or (1'B)'2' for a Mason Bogie).

This type of locomotive was one of the more common configurations for Mason Bogie locomotives, like those used on the Boston, Revere Beach and Lynn Railroad.