The design is flawed
Out of the package they look very nice, good finish etc... When taking the screws out of the rings, one screw was tight, too tight. There was either a piece of metal or the screw was over torqued, and there was a little damage to the thread on that screw. It was no big deal and cleaned up with the touch of a file.
Because the top portion of the rings are longer than 180*, they have to be stretched open around the tube of the scope. They are springy enough, but one of the rings scratched the tube in the process. Therein lies the flaw. They should have chamfered the inside edges of the square corners for accommodating that slide over the barrel, or a thin piece of Teflon strip for the install. I was as careful as I could be realizing the potential for this to happen, but it still scratched it. Other than that, they fit on my model 60 Marlin without any additional tools or parts.
If you have a 40mm. bell on your scope, 1" tube, and you intend to leave the rear sight on, you will need to get the 1.115 variant. To get eye relief correct, I had to remove my sight. I got the .99 height one. That's alright though, because the scope is real low to the bore and seems to fit the rifle very well.