Remember these? ...."The Mullard Expandabox Units have been designed after careful study of dealers' stocking problems to store valves neatly and methodically."
Mullard went on to say...."Each unit is specially sectioned to allow valves to be easily withdrawn and to prevent small valves being pushed through to the back. The uniform height and depth of the Units enable those containing valves of varying size to be stacked side by side."
A further revalation was..."The space and shelving facilities at your disposal present no difficulties in the case of Expandabox valve stocking as odd spaces can be filled by stacking units horizontally and the robust construction of the Units enables large quantities of valves to be stored without any special shelving with a metal clip holding each Unit perfectly rigid."
A quite prescient pont made before the days of kan-bans, home (or shop) computers was.... "The Expandabox Units provide an automatic stock control for whenever a valve is withdrawn an obvious space is left. The job of re-ordering valves is further simplified by indicating the appropriate valve type numbers inside each honeycomb section and bright yellow labels (just like the ones Mullard Magic uses for valve data records!!!) have been designed for this purpose."
And all this was available in a unit holding three, four, five or twelve valves - each holding the requisite standard sized Mullard cartons for just sixpence and were a jolly good product for the tidy workshop conscious valve hoarder:-
These were a well established workshop aid by the late 1950s and during 1958, the Mullard technical services group received a letter from a worried chap in Halifax enquiring about the purchase of Expandaboxes to construct a nuclear fallout shelter. Questions were raised about how best to secure the Expandabox stacks to the exterior of a sturdy oak dining table - was passe-partout tape and chicken wire or Seccotine the most suitable fixative? Unfortunately I don't have Mullard's reply to hand.