This will allow you to mount the Trijicon RMRcc directly to your slide. Due to the small size of the 43/43x/48 slides it will remove your rear dovetail on those slides, and since the RMRcc does not have any integral iron sights, you will need to mill a new dovetail in front of the red dot if you want back up irons. On the standard Glock frame (double stack 9mm, .40, .357) your options include keeping the factory dovetail, race cut, or adding a new dovetail in front of the optic. If you are doing irons in front of the optic please send your sights with the slide or purchase them from us. We will mount and align your sights and red dot if you send them with the slide.
Again, the RMRcc can only be milled with irons forward or Race cut on the 43/43x/48. We are not modifying the MOS version at this time.