Large quantities of ventilated vans were built by British Railways in the 1950s as they gradually took over traffic that had previously used sheeted open wagons. After completing outstanding orders to regional designs which they had inherited in 1948, construction of vans to a standard BR design started in February 1951. These were single vent vans with corrugated steel end walls, as per LMS and LNER designs, but with a pair of hinged doors each side, as used by the GWR and SR. Bodywork changed from planked to plywood, or a combination of both. The vans were built mainly at Wolverton and Darlington, but at least three batches came from Ashford and two batches were supplied by outside contractors, Charles Roberts Ltd and Pressed Steel Ltd.

Our model 373-627 is based on a van built at Wolverton in 1957-58. These had planked sides and plywood doors. It is seen in early bauxite livery and numbered B773727.