FN America FN 509 Midsize MRD, Semi-automatic, Striker Fired, Mid-Size, 9MM, 4" Barrel, Polymer Frame, Flat Dark Earth Finish, 2-15Rd, Ambidextrous Controls, Non-Manual Safety, Optics Ready 66-100741 • Double Action • Capacity: 15+1 • Finish: FDE • Sights: Black Co-Witness • Barrel length: 4 • Overall length: 7.4 • FN Optics Mount System/ Interchangeable BackstrapsInterchangeable Backstraps FN Optics Mounting System Midsize Frame • Action: Striker Fired • Capacity: 15 + 1 • Finish: FDE • Sights: Black Co-Witness Iron Sights • Barrel length: 4" • Overall length: 7.4" • 15in Free-Float MLOK Rail/ Ambi Bolt Release