That is a Traditions Performance Firearms offset mount. No longer made, but is essentially the same as offset rings. The hammer does not have to be bent as long as the eyepiece isn't too large. One thing with the Leupold scope is that it didn't have enough adjustment to adjust for the offset mount, and I had to use windage adjustable rings. That is the only scope I used where I ran into that problem. A Nikon and a Tasco were fine.