I'm not sure. Ice reached out to him about it. The nipplea on the mount I got is to narrow for the holes to line up. From center nipple to center nipple in the front his was between 3/4 and 7/8 but closer to 3/4. On the ff3 picatiny that come with the sight its between 3/4 and 7/8 but closer to 7/8.