The GLOCK 23 Gen4 in .40 introduces revolutionary design changes to the pistol that combines compact dimensions for both open and concealed carry with minimum weight-despite its large magazine capacity. The Modular Back Strap design lets you instantly customize its grip to adapt to an individual shooter's hand size. The surface of the frame employs the new scientifically designed real-world-tested Gen4 rough textured technology. Internally the new GLOCK dual recoil spring assembly substantially increases the life of the system. A reversible magazine catch changeable in seconds accommodates left or right-handed operators. The G23 Gen4 in .40 caliber retains the GLOCK accessory rail for your attachments.