This was exactly what I needed and couldn’t have been easier to install. I bought the cmore sts, the mount designed for that optic, popped off the sight and mounted the red dot. It required a couple of bits, locktite and a fat wrench to get the torques right. In about 10 minutes I went from ISR to OSR. If you can run a screwdriver you can make the same modification using this mount from Allchin and TK.