I don't think it matters: AFAIK threadless BB have tapered cups, so fit any size shell.
Surprised if a Carlton had an Italian BB; either way, one just won't fit the other.
Check Sheldon Brown for a handy table which explains what happens if you try to mix shells and cups.
@Scilly.Suffolk started
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I don't think it matters: AFAIK threadless BB have tapered cups, so fit any size shell.
Surprised if a Carlton had an Italian BB; either way, one just won't fit the other.
Check Sheldon Brown for a handy table which explains what happens if you try to mix shells and cups.