CMP Box Covers
I'll take a stab. Advent of thermal plastics, i.e., bakelite, etc., was a mere science pre WW2. Hostilities pushed plastics production way ahead, accellerated it.
Was it not the prewar norm for box covers to have a simple canvas view "flap" if any at all ? Prewar Hillmans, Austins, early Morris truck pics show canvas covers with tied flaps, but I'll be damned if none are shown rolled up to exposed the clear plastic sheet, if it was there.
Cheerio, Johnnie.
|