No picture of the mouth piece. If I knew what the mouth price looked like I would be able to easily figure it out, haha. I was hoping someone on here recognized it just from a side view. No particular desire other than being curious. I’ve seen it on a few horses and wondering it’s purpose. As for large D rings, I’ve always used them. I personally haven’t had any issues with them digging into the sides of the face. Also not sure of this bits pinching potential. Simply inquiring about what it actually is.