Glock's G34 Gen4 in 9x19mm introduces revolutionary design changes to the "Tactical/ Practical" to have the same OAL as 1911 Government pistols. The Modular Back Strap design lets you instantly customize its grip to adapt to an individual shooter's hand size. Its frame employs a scientifically designed, real-world-tested, Gen4 rough textured technology. Internally, the dual recoil spring assembly substantially increases the life of the system. A reversible enlarged magazine catch, changeable in seconds, accommodates left- or right-handed operators. The Glock Modular Optic System (MOS) simplifies the mounting of popular optics without costly custom machining of the pistol's slide. MOS has four plate options to comply with the specifications of some of the most trusted optic manufacturers in the industry, and a cover plate when no optic is mounted. MOS gives you the option of adding tall iron sights allowing the optic and the iron sights to co-witness. This G34 Gen4 MOS Competition model has a black frame with a black slide, adjustable sights, and a 17-round capacity.