Icame up w/ the idea for that mount and made a deal w/ Excal to mfgr and sell them. My prototype did not have the rubber dampening system that the one they offer has. I took 1200 plus shots out of an Excal Emax w/ it before sending it to Excal. I used the cheapest RF Bushnell sells. Would still be using that one, but on a hog hunt in La the dang mount came off the scope on the back of my 4 whlr, lol. make sure your ring/mount screw stays tight!!