For Trijicon RMR – Apex Optic Mount Screw Set for FN MRD Pistols with an Apex mount for RMR Footprint Optics

This Apex Optic Mount Screw Set is a dedicated replacement or spare fastener kit for securing a Trijicon RMR or other RMR-footprint optic to an FN MRD pistol equipped with an Apex optic mount. The set solves the common problem of stripped, lost, or mismatched screws during optic installation or maintenance—ensuring a consistent, repeatable torque spec and a zero-shift-free interface between the slide and the optic. Each screw is precision-machined to match the thread pitch and length required by the Apex mount, eliminating guesswork and the risk of over-threading into the slide.

Compatibility

• FN 509 series (all MRD variants with Apex mount installed)
• FN 509 Compact
• FN 509 Tactical
• FN 509 Midsize
• FN 545 (MRD models with Apex mount)
• FN 510 (MRD models with Apex mount)
• Requires Apex optic mount for FN MRD pistols (sold separately)

Key Features

• Thread pitch and length matched specifically to the Apex mount for FN MRD pistols
• Heat-treated alloy steel construction for corrosion resistance and repeated torque cycles
• Includes (2) screws—sufficient for a single optic installation
• Compatible with Trijicon RMR (Type 1, Type 2, RM06, RM07, RM09) and Holosun 407C/507C/508T (RMR footprint)
• Standard hex-head (3/32” or 2.5mm) for use with a torque driver

Install Difficulty: 1/5

Tools required: 3/32” hex driver or 2.5mm ball-end hex key, torque wrench (recommended 15-18 in-lbs), blue Loctite 242. No fitting, filing, or modifications required. Simply remove existing screws, apply thread locker, and torque to spec. Estimated time: 5 minutes.

FAQ

Will these screws work with a factory FN slide without the Apex mount?

No. These screws are specifically designed for use with the Apex optic mount for FN MRD pistols. Using them with a factory mounting plate may result in incorrect thread engagement or insufficient thread depth.

Can I reuse these screws if I swap optics?

Yes, provided the screws are not stripped or deformed. Inspect threads visually before reuse. Always apply fresh Loctite and torque to 15-18 in-lbs. We recommend replacing screws after 3-4 removal cycles to maintain consistent torque.

What is the thread pitch and length of these screws?

These screws are M3 x 0.5 pitch, 6mm length. They are identical to the original screws included with the Apex mount kit. Verify your existing mount uses the same spec before ordering.

Shipping: Ships same business day if ordered by 2 PM EST. Flat rate $4.99 USPS Priority, free over $75. Warranty: This component is covered by a limited lifetime warranty against manufacturing defects. If a screw strips during normal installation, contact us for a replacement set.