Prior to rail nationalisation cement was bagged and transported in covered wagons. However, with post war construction moving apace, efficient bulk transportation was needed. In 1954 the pressure discharge bulk powder wagon, known as the Presflo wagon was developed.
This bulk handling cement wagon had a capacity of 20 tons (later increased to 22 tons) and was gravity fed from the top but was efficiently discharged under pressure via pressure hose and valves at one side of the wagon. Five different factories were involved in the construction of the total 1920 Presflo cement wagons produced between 1955 and 1961 and the design was so successful that their final withdrawal from service was only completed in 1987. Several examples of Presflo survive into preservation.