This Apex Optic Mount is designed to securely mount the Holosun 509T to the slide of the Sig Sauer P320 Legion, P320 M17/M18 and other models featuring the Sig-LOC optic cut. It is machined from a billet of steel and Black Oxide finished.
The fully integrated rear sight in front of the optic acts as a gas shield to keep your optic glass cleaner longer and saves labor from needing to install a rear sight.
The integrated rear sight is setup to co-witness in the bottom 25% of the optic window. Requires a tall front sight for co-witness(Included). Two different sight height packages available. Select option based on barrel length (see below).
The rear sight behind/after optic versions include a blast deflector that is not visible through the optic.
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