The K22 X-Trim Mk23 is the little brother of the 9mm X-Calibur. The pistol features a slide design with more aggressive serrations; fiber optic front and rear sights; optics ready slide; interchangeable back straps and a two-spring system to tune for any ammo you choose. Includes three 10rd magazines, three Interchangeable Backstraps, trigger lock, bore brush, owner's manual and four optics plates compatible with Vortex Venom/DocterNoblex/MeoRed 30, Trijicon RMR, CMORE STS2, & Shield SMS).