I used to be a shipfitter in Seattle area shipyards. We always used Airco torches. I stopped doing that work in 1980 and have never gone back, although I still own an Airco cutting torch which I use with my O/A setup. Today I responded to a local ad and went over and bought a whole box of "stuff" for $20. It has the oldest welding torch I've ever seen, no tips for it, installed is a really ancient cutting attachment, might work, dunno. Probably go in the scrap brass bucket. Also got a pair of Smith regulators, look like real nice ones but they're a little sticky. The oxygen regulator, on my tank, creeps up steadily. It does seem to hold a nice flame on a welding torch, but there's clearly something stuck inside. Might be 2-stage regulators. Those are also dunno items, probably worth a few bucks, or maybe more after a rebuild.
But the stuff I'm writing about is there was about a 6x6x6" box *full* of new Airco torch tips. None of these are welding tips, they're tips that will fit on my torch. And most of them are *huge*. Ever see a type 144 cutting tip, number*twelve*? Thing looks more like a brass cannon! A whole pile of flushing tips, bulkhead tips, and huge cutting tips, all NOS in Airco packaging.
In the end there are about six usable cutting tips in there I'll probably use, along with a few bigger tips I'll keep around in case I need to hack off something gigantic or just to look cool. OK deal for $20.
I can't even imagine what you might try to cut with a No. 12 tip. The cutting orifice is nearly 3/16" diameter. Wow.