Richard, the box you are thinking of is the
H. 50 and the
H. 51. The H. 50 is the metal outer box as you describe and the H. 51 is the wooden inner box. They were both introduced at the end of WWII as the "Jungle Pack". I am desperately trying to find out if they were used by troops in Europe as most people seem to think. I have lists that "suggest" they they weren't in use in Europe. If anyone can supply an In Service date I would be most grateful. It is entirely possible that the two boxes were introduced at different times for different purposes. The H. 50 is still in use today.