Open wagons had long been a principal merchandise wagons on Britains' railways, even though the percentage of covered vans had increased steadily British Railways still found a need for new open merchandise wagons in the 1950s.
- Accurately moulded body and chassis
- Self-compensating chassis for smooth, trouble-free running
- Sprung metal buffers
- 3 link chain or instanter coupling and sprung coupling hook
- Finely profiled wheels and axles with pin-point bearings
British Railways Ideal Stocks Committee favoured the LNER all-steel design wagons as the standard high sided open merchandise wagons, but recognised that the all-steel wagons proved unsuitable for some traffic and wooden bodied wagons would also be required. Wood body wagons noticeably suffered from damage to the end planking as loads shifted, often during shunting. The LMS had addressed this issue with robust corrugated steel end panels and as BR sorted out the left-over pre-nationalisation building programmes diagrams 1/039 and 1/044 appeared as the first of the BR design 5-plank wagons to be built in large numbers.
5,650 wagons were built to diagram 1/039.