Here a picture.
It's not quite as big as I thought.
That bore is for the bumper.
As I told you in the other thread with the exact same question, they vary dimensions to hit target weights.
I ordered a 60" sneaky from them some years back, and did not know this. The plan was to use Predator 314 shafts I already had. When the cue showed up, the joint was .870-.880 if memory serves (standard for a 3/8 10 should be .850), and the butt diameter was way oversized as well, cant remember the exact measurement, but was very noticeable in the hand.
I then asked about supplying measurement specifications, and they said no problem. So I have gone that way since. I have 5-6 customs from them.
I called them and got the answer at that time (2015ish?). I gave you the answer that Dave Schmelke gave me.