As I've been inspecting labels, I've seen one on several packages that I don't recognize. It is a small cylinder (shaped kind of like a tuna can) with a number followed by the letter "m." For example, inside the cylinder, it would say "12m." Just above the cylinder, there is what looks like an open can lid -- as if you were lifting the top off of a can of tuna.
This symbol appears on things that aren't in cans, so I don't think it has anything to do with a can.
Anybody know what it is? I'm not even sure how to google this particular symbol!