To install your Trijicon RMR red-dot sight, first remove the rear sight from your firearm and replace it with the EGW mount. The mount can be removed and the rear sight reinstalled at any time. All necessary mounting hardware is included. The EGW mount facilitates the straightforward installation of a Trijicon RMR red-dot sight on Smith & Wesson M&P Shield EZ models by substituting the rear sight This mount is incompatible with standard Smith & Wesson M&P, M&P 2.0, and M&P 22 models The package includes mounting hardware The mount is detachable for rear sight reinstallation, requiring a 5/64 inches Allen wrench for the screws