What's your guess on what this is?

[Mary Ann]

https://www.ebay.com/itm/285550757343?h ... SwBAZlTFj3

Seller is goodwill I think, and probably won't even know how to find out what key it's in. No useful data in the listing.

[edfirth]

It's a 186 BBb but as to exact vintage Who Knows? Best, Ed

[TheHatTuba]

There's a really old 186 BBb also on the bay right now.

[DonO.]

Even though fuzzy when enlarged, I believe the bell engraving has the “Mirafone” spelling. That helps to narrow down the age. Late ‘60’s-mid 70’s?

[Mary Ann]

Seller says she inherited from her husband and is willing to do a video conference with me, but if no one is there to play it that seems a bit pointless. It could be a gem or a dog, and no way to tell. With the offer of a video conference the seller is likely legit.

[bort2.0]

Nice little gap between the kranz and the bell in photo 1....

[bort2.0]

There's a really old 186 BBb also on the bay right now.

I've seen older.

[jtm]

Even though fuzzy when enlarged, I believe the bell engraving has the “Mirafone” spelling. That helps to narrow down the age. Late ‘60’s-mid 70’s?

My mid-80s 188 also says MIRAFONE, both on the kranz and in the little triangle on the bell. It also says “Made in Germany”, despite being from before unification.

If that tuba is from the 60s or 70s, the serial number should narrow it down.

[bloke]

Relacquered look, busted bell, full retail used good condition type of price... I scrolled right past it.