C&H PLT 320 X-FIVE TO HOLO 509T

Description

This steel adapter plate from C&H Precision Weapons is built for competitors and serious shooters running a SIG P320 X-Series or M17/M18 slide with an existing Romeo1Pro or DPP factory cut who want to mount a Holosun 509T without sending the slide out for additional milling. The plate bridges the footprint difference between those two cut patterns, letting you run the 509T’s larger window on a pistol that was never originally configured for it.

The plate itself is machined from mild-grade steel and finished in MIL-SPEC Type III hard anodized black — the same specification used on military and law enforcement issue equipment. Steel construction keeps the plate thin enough that the 509T sits at a practical height while adding meaningful rigidity compared to aluminum alternatives. At roughly .095 to .099 inches thick, it contributes very little to overall slide weight, which matters when you’re balancing a competition pistol for recoil management. All mounting hardware is stainless steel, and because the screws are standard replaceable fasteners, a stripped or damaged screw doesn’t mean replacing the whole plate.

C&H Precision machines each plate on HAAS CNC equipment and runs it through multiple quality checks before it ships from their shop in Coastal Georgia. Mounting hardware is included. Note that this plate is not compatible with the Holosun HE509-RD ACSS Vulcan variant — only the standard 509T footprint fits correctly. If you’re uncertain about iron sight height after mounting, C&H recommends contacting their support team, since co-witness compatibility depends on the specific combination of slide, plate, and optic in use.