Heh, kind of appropriate that I should reply to this thread. However, frustratingly I can’t remember the exact details. What I do remember is that back in the 1980s (?), a certain pack of Nabisco brand biscuits featured an explanation of the red-triangle device (i.e. this version). Unfortunately I can’t even remember which type of bicuits it was on :smack:
It certainly wouldn’t have been Oreos, as we didn’t have them in the UK until quite recently. I think it was a savoury cracker…