The baucher has an eggbutt like ring at the mouthpiece for the rein, with an upper cheek that has a ring at its end, to which the cheekpieces of the bridle are attached. The mouthpiece does not slide on its ring.
This bit lays flat against the horse's mouth and is quite fixed in the mouth concentrating pressure on the bars. This bit results in slight poll pressure.

Ring Size: 2"
Cheek length: 3.5"
Mouth Thickness: 14mm