Apex Optic Mount for ACRO/MPS* – FN MRD

The Apex Optic Mount for ACRO/MPS* – FN MRD is a steel billet mount built to lock Aimpoint ACRO P-1, P-2, Steiner MPS, and Lead & Steel Pandora PB-3 optics directly onto FN 509 slides with the FN Low Profile Optics Mounting System. Machined from solid steel and finished in black oxide, this mount eliminates the need for stacking plates by integrating a locking key that engages the slide without an MRD insert. Per Apex Tactical specs, the mount weighs 0.8 ounces and holds zero under recoil, making it a straightforward upgrade for shooters who want a secure, low-profile optic interface.

Manufacturer	Apex Tactical Specialties
Model	Apex Optic Mount for ACRO/MPS – FN MRD
Material	Billet steel (per manufacturer specs)
Compatibility	FN 509 models with FN Low Profile Optics Mounting System; Aimpoint ACRO P-1, P-2, Steiner MPS, Lead & Steel Pandora PB-3, any ACRO-footprint optic
Finish	Black oxide
Weight	0.8 ounces (approx.)
Condition	New

Key Features

• One-Piece Steel Construction — Machined from a single billet of steel, this mount resists flex and holds zero better than multi-piece aluminum plates. The black oxide finish adds corrosion resistance without adding bulk.
• Integrated Locking Key — The mount’s built-in key engages the FN slide directly, so you don’t need a separate MRD insert or adapter. This reduces parts count and eliminates the stacking-plate setup that can loosen over time.
• ACRO/MPS Footprint — Designed specifically for Aimpoint ACRO P-1, P-2, Steiner MPS, and Lead & Steel Pandora PB-3 optics. If your optic uses the ACRO footprint, this mount fits without shims or modifications.
• Low-Profile Fit — The mount sits flush with the slide contour, keeping the optic close to the bore axis. This helps maintain a natural sight picture and reduces snagging on holsters or gear.
• No Stacking Plates — By replacing the factory plate stack with one solid steel mount, you remove a common failure point. Fewer screws and interfaces mean less chance of loosening under recoil.

Who It’s For

This mount is for the traditional shooter who wants a reliable, steel-mounted optic on their FN 509. It suits those who prefer a fixed, low-profile setup over adjustable plates — shooters who value simplicity and durability over modularity. If you run an ACRO, MPS, or Pandora PB-3 and want a mount that won’t shift or break, this is your pick.

Pros & Cons

• Pro: Solid steel construction outlasts aluminum plates under heavy use.
• Pro: Direct-fit locking key eliminates extra parts and potential loosening.
• Pro: Low-profile design keeps the optic close to the slide for consistent accuracy.
• Con: Limited to ACRO-footprint optics only — not compatible with RMR, DPP, or other patterns.

Comparison vs. Competitors

Feature	Apex Optic Mount (Steel)	Zev Technologies PRO MRD Plate	Agency Arms AOS Plate
Material	Billet steel	7075 aluminum	Steel
Optic Footprint	ACRO/MPS only	RMR, DPP, ACRO (swap plates)	RMR, DPP, ACRO (swap plates)
Installation	Direct-fit locking key, no inserts	Requires separate plate for ACRO	Requires separate plate for ACRO
Weight	0.8 oz	1.1 oz (with ACRO plate)	0.9 oz (with ACRO plate)
Price	$60	$85–$100	$75–$90

FAQ

Will this mount work with the FN 509 Compact or FN 509 Tactical?

Yes, it fits all FN 509 models that use the FN Low Profile Optics Mounting System, including the Compact, Tactical, and standard 509. Verify your slide has the factory mounting system before ordering.

Does this mount include screws for the optic?

No, the mount does not include optic screws. You will need to use the screws provided with your optic or purchase the correct length for your ACRO/MPS. Apex recommends Loctite 242 for installation.

Can I use this mount with a red dot that has a different footprint?

No, this mount is designed exclusively for optics with the ACRO footprint (Aimpoint ACRO P-1, P-2, Steiner MPS, Lead & Steel Pandora PB-3). Other footprints like RMR or DPP will not fit.

Is this mount compatible with the FN 545?

Yes, the FN 545 uses the same FN Low Profile Optics Mounting System as the 509 series, so this mount fits the 545 as well. Confirm your slide has the factory mounting system.

Does the black oxide finish wear off quickly?

Black oxide is a durable finish, but it can show wear over time with holster use. It’s more corrosion-resistant than bare steel but less so than Cerakote. Regular cleaning maintains its appearance.

Trust & Delivery

• ✅ Nationwide delivery (all 50 states)
• ✅ Ships 1-2 business days
• ✅ 30-day returns
• ✅ Secure checkout

Explore more optic mounts in our FN 509 Parts and Optic Mounts categories. For the FN 545, check our FN 545 Parts section.

Last updated: April 2026