I have no idea, and don't care.
I've been selling a lot of JP - to otherwise-yamabots (schools/teachers who spend OPM), due to that "supposedly" being the case, but whatever...
I'm not bothering to check, re: this mouthpipe.
I already know that they're pricey, I don't want to wait for one, and I want to get paid for this particular school's stack-o'-beat-up horns.
If someone's going to make a bunch of dough on labor, I'd rather it be ME, rather than a Japanese corporation (off of Japanese or Yamachinese labor).
The Wisconsin place was temporarily out-of-stock (now: back in stock) re: the best-candidate generic/bend-to-fit mouthpipe for this tuba, but York-aholic had an oddball one which he didn't need, it's shorter than the Wisconsin thing, but is barely long enough. He sent it. THANKS! BTW, @York-aholic, I think I found some stuff in my King junk-box that you might like - and I do not need.
I WAS going to - simply - fabricate/install a PERMANENT mouthpipe tube (as they don't march with this thing), but the geometry of the entry port (into the #1 casing) defined that actually just making a replacement DETACHABLE one as easier than making a no-detachable-hardware one, so...
Anyway...The receiver is a something that a pro had (along with a few others and whole bunch of other parts junk I bought from them a while back...I had to shim the back, as it was set up (probably?) for a gigantic 2165 'pipe, but I found some tubing that would fit very tightly into the back (perfect fit - actually had to pound it in there) and shimmed it down to "normal" mouthpipe receiving size.
The 90-degree elbow is from a Yamaha-321 - one of those soldered-in thingies that goes from a slide into one of the top-action valve casings. I chopped the funny final curve off of it.
The male receiver is a Yamaha outside slide tube (same O.D. as their receiver part)...
...and I had some of that crappy Yamaha detachable hardware leftover (new) from repairing a bunch of that crap in the past...
...so voila.
It's got little bend marks (you can see them), but they're very minor. I ain't gonna tap, I ain't gonna file, I ain't gonna sand, and I ain't gonna buff...
This is a BEATER horn, and they are not paying to un-smash the bottom bow - so this mouthpipe looks like a jewel, compared to everything else...and this is the WRONG time of the year to be hand-making detachable tuba mouthpipes, and - based on typical abuse - NO metal should be removed from this thing: NONE...so this is marked
DONE. Oh yeah:
This wasn't very much fun.
bloke "$ummer repair$"