Install EGW red dot mounts from left to right with the muzzle facing forward. The tapered dovetail simplifies the process. To use with your Vortex Viper/Venom, Burris FastFire or Docter sight, just remove the rear sight and insert the EGW mount. It's fully reversible and all mounting hardware is provided. EGW red-dot sight mounts substitute the rear sight on CZ P10C or P10F models, enabling the installation of Vortex Viper/Venom, Burris Fastfire, or Docter optics The mount features a progressive dovetail design for easy installation, allowing for the original rear sight to be reinstalled at any time The package includes mounting hardware however, altering the firearm may void the manufacturer's warranty and should be performed by a qualified gunsmith