The FN 509C MRD pistol in FDE with a 3.7-inch barrel and 10-round capacity (brand part no. FN 66-100575) is a compact 9mm cut for a mini red dot optic, with a magazine configuration built for added-regulation states. FN America serrates the slide over an FDE polymer frame, and all-black co-witness iron sights line up with a mounted red dot for a consistent sight picture. Two 10-round magazines are included. Among optics-ready semi-auto handguns, this 509C MRD configuration favors concealed carry in added-regulation states.

Key Specifications

• The chambering is 9mm.
• The capacity is 10 rounds.
• The barrel measures 3.7 inches, finished in FDE.
• The slide is optic ready and serrated, cut for a mini red dot.
• The sights are all-black co-witness iron sights, aligned with a mounted optic.
• Two 10-round magazines are included, built for added-regulation states.
• Shipping weight of approximately 3.15 pounds.
• The action is semi-automatic, cycling a fresh round into the chamber with every trigger pull.
• Equipped with a No safety.

Frequently Asked Questions

What do co-witness sights provide? A consistent iron sight picture that lines up through a mounted red dot optic.

Why does this configuration use 10-round magazines? It’s built to meet added-regulation state capacity requirements.

Buy the FN 509C MRD Pistol, FDE

Compact, optics-ready carry performance with co-witness sights is exactly what this 509C MRD delivers. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL.