The FN 509 Midsize is a striker-fired 9mm pistol with a 4-inch barrel and a 10+1 capacity in the supplied configuration. It has a polymer frame, an optics-ready slide and three-dot sights. The pistol has no manual safety and uses an integrated trigger safety. It weighs 25.5 ounces and measures 7.4 inches overall. Two 10-round magazines and two backstraps are included.

This midsize pistol suits buyers who want a 9mm that is easy to conceal but still handles with the control of a larger gun. The flat-faced trigger gives a consistent, controllable press. The textured backstraps help with grip security and recoil management for range use or everyday carry. The sights are three-dot, and the optics-ready slide accepts a compatible red dot for owners who want one. The two supplied backstraps let the grip be set up for different hand sizes.

Key features

• Striker-fired action with integral trigger safety
• Optics-ready slide with three-dot sights
• Flat-faced trigger for a controllable press
• Two textured backstraps included
• 10+1 capacity, 25.5 ounces

Firearms ship to the FFL dealer you choose, where you complete Form 4473 and the background check.