Inside diameter is 1.575" (40cm) and outside width is 1.72" (44cm). Troy rails are normally 1/8" longer than listed.
Just FYI... Inside is milled round and not hexigonal like the outside and receiver end is milled to fit standard barrel nut, usually not pictured anywhere.
The rails also have a small receiver stop on the left side to keep aligned.
It's kind of what you get as far as the logos.
Sometimes they are pictured filled in white, but come non-painted... sometimes, show painted, but come non-painted. Some come with VTAC logos. Logos on right side only.
Have two factory-built (14.5" with 11" Troy MLOKs) that were painted (on right side) and have the painted Troy circular horse logo (on left side).
I mostly have Troy rails and now going from quads to putting on MLOK rails. Having bigger hands, the slightly wider rails with MAGPUL rails covers are very comfortable.
Lock-up is tight and they are simple to install.
Primary Arms usually has the best prices on Troy rails. Now at $159.99 but if you wait for their next good sale, it will be $20 cheaper ;)
Good Luck!
me