Shadow Systems XR920, Foundation, Striker Fired, Semi-automatic Pistol, Full Size, 4" Barrel, Polymer Frame, Nitride Finish, Black, Steel Sights, Optics Ready Slide, 17 Rounds, 2 Magazines, Includes (3) Backstraps and Optics Kit SS-3306 • Capacity: 17+1 • Finish: Black Matte • Sights: Dot Front Sight/ Serrated Rear • Barrel length: 4 • Overall length: 7.5 • Optic Cut for RMR & Holosun/ Billet Slide PartsOptics Ready Foundation Slide Polymer Guide Rod/Optic Plate Flat Face Polymer Trigger • Action: Striker Fired • Capacity: 17 + 1 • Finish: Black Nitride • Sights: FS: White Dot RS:Black • Barrel length: 4" • Overall length: 7.13" • 15in Free-Float MLOK Rail/ Ambi Bolt Release