Peter Rogers asked:
> Was the Vitus 172 series a good tube set?
> Was it available in double-butted and plain gauge?
> Is it seamless?
My recollection (must be considered unreliable until you get confirmation) is that 172 was DB 1.0/0.7mm (same weight as Columbus SP), seamless, and some alloy, probably normalized 4130 or similar. It was a step up from their Durifort line. I doubt they would have made a plain-gauge 172 variant under the same name, but it would be hard to prove they never did.
Seattle, WA USA