This is not a tuba or euphonium, but it is a cool old instrument. I'm listing in case someone here wants to fool around with one. The Coast Guard Jazz Ensemble ("The Cutters") had a solo trumpet player who was creative. He used one of these sometimes (I think it was in Eb) and sounded great. Or it would make a nice wall hanging! Price is only $230 and the horn is in nice shape (or I would not have bothered).

https://www.ebay.com/itm/264346056260

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