I'll help best I can. I've had 10, or is it 11, Billato built bikes over the years.

My Concorde had the 3E which I'm not sure if I ever found out for sure it was Aelle tre tubi but I sure suspected it was.



All the Lemonds I had were marked as you've indicated. Tubing type stamped under the frame size stamp:


Ventoux in Cromor

Maillot Juane in TSX, I also have a Team Z marked the same way.

Team Gan no picture of BB but had a "GLx" stamp. The GL looked to be one stamp with a smaller out of line x next to it.

The Giordana's are not consistent.


Antares in Cromor

Neither Podium tubed Giordana XL Supers is stamped:




Unfortunately, I don't have any underside BB shots of the SLX Polaris or the SL Scorpius. I can't remember if they were stamped or not.

I also have the shot of the NOS Giordana ECO tubed fork I got from Gita with the one XL Super Frame. ECO was in between the Cromex and Podium tubing, the second best per say.