The vent has a flat piece on the bottom that keeps it from rotating. It is very tight to get in. I asked the seller if he could make one without the ball for the passenger side. One so they'd match, but more importantly his vent flows better air through it than the factory vent on the passenger side.
The ball on the vent mount is a 1". The Bullet Point 1" adapter doesn't fit it well. I'm using one of the BP 20mm.
The vent has a flat piece on the bottom that keeps it from rotating. It is very tight to get in.
Here is exactly what I got installed now with the BP phone holder.
https://www.amazon.com/dp/B0CCX8CMDM?tag=wranglerorg-20