Not in the fitment guide (yet), but it fits great on the RMR plate for the Alpha Foxtrot Romulus 45acp 4.25 Comp. Be sure to pull the plate off, add threadlocker (not done at factory), and retorque before installing optic. 9.5mm screws are perfect. Zeroing was super easy, laser boresighted first and was on paper right away, about one clip to dial in. Green dot is easier for me to see and having the ring really helps these eyes acquire the target. Installing the optic also makes it easier to manipulate and hold the slide, especially for field stripping.