In 1948 the Railway Executive appointed the Ideal Stocks Committee to report on the most ideal stock for probable traffic in 1950. For general merchandise traffic, the 12 ton van and the 13 ton open were the preferred design. The vans were to have hinged rather than sliding doors and 10% of open wagons should be fitted with sheet support bars.

The Dapol corregated five plank wagon features:

Accurately moulded body & chassis

Self-compensating chassis for smooth trouble free running

Metal sprung buffers

3 link metal coupling chain and sprung coupling hook

Finely profiled wheels and axles with brass bearing pockets

Fine application of livery