Hi, I picked up this frame recently and was told it was a Basso but the seller knew nothing else about it...

It doesn't have a maker's name anywhere, all I have is a 'B' logo on the head tube which doesn't look like any Basso logo I can find, a serial number on the bb, and a columbus zonal sticker.

Photos attached.

Is this a Basso, or something else?

Cheers!