Anyone know what’s up with this tuba? Anyone heard of this?

https://reverb.com/item/87617254-used-e ... t=87617254

Hey folks,

I’ve been out of the game for ten years. I graduated with a tuba degree in church music. I work in church, so I don’t get to play much, but we’ve got a concert in a few months where I’m expected to solo. So yeah..

I’m looking to buy something cheap, like no more than $1,500, but ...

Thanks y’all!

Anyone know how the compensating system works without the 4th valve?
https://www.facebook.com/share/p/1ESNpycRVg/?