Given the intended purpose of carrying such a dangerous commodity, the Railway Clearing House (RCH) produced a standardised design in circa 1930 which was was soon adopted by the Great Western Railway (GWR), London and North Eastern Railway (LNER), London, Midland and Scottish Railway (LMS) and Royal Ordnance Factories (ROFs)* with minor detail differences.
The low height vans were made of all metal bodies lined with a combination of lead and wood. A cast metal plate on the external doors instructed staff that no unauthorised persons were permitted to open the doors and nail-less over boots must be worn to minimise the risk of sparks.
During peacetime, up to five vehicles were permitted to be marshalled together, however during wartime this was relaxed owing to the greater quantities of explosives requiring transport.
Following Nationalisation in 1948, British Railways (BR) continued to build a slightly modified version under Diagram 1/260.
The most striking aspect of Diagram Z4-'Cone', No 105777 (902004), is the roof which is incredibly thin and replicates steel sheet superbly. The GWR iteration had a greater overhang compared to others which is faithfully replicated and includes fine banding and rivet detail.
The remainder of the van is equally crisp with fine locking latches and retaining chains which again vary between each company.
The GWR satin black livery with red cross is neatly applied with precise lettering and clearly legible detail on the builder's plates. Positioning of some of the text is however known to be incorrect (having been copied from a preserved example).
The underframe is equally detailed, with a comprehensive representation of the brake gear. The first sixty-five wagons constructed to Diagram 1/260 were unfitted, however survivors were retrofitted with vacuum brakes which have been included in the range - these examples feature the lower placement of the vacuum cylinder in the chassis, common with conversions, and vacuum pipes.
Dished three-hole wheels run within metal bearings, with split-spoke for the LNER and ROF.
Priced at £32.95, the RRP need not be justified - the continued increase to the cost of living has been made abundantly clear in the wider press and in this instance the quality of the product is more than appropriate given the build and finish.
*Collective name given to the UK Government's munitions factories in, and after, the Second World War.