The G41 Gen4 is a practical-tactical .45 caliber pistol designed to maximize sight radius while improving weight distribution and balance. It is built with a G34 slide width on a G21 Gen4 frame and is 1.5 ounces lighter than the G21 Gen4. The longer barrel and slide on the G41 Gen4 help to reduce muzzle flip and felt recoil, while the longer sight radius makes it more accurate for competition or duty use. The surface of the frame employs the scientifically designed, real-world-tested, Gen4 rough textured technology. The modular backstrap design lets you instantly customize its grip to adapt to an individual shooter's hand size. Glock engineers have developed the Glock Modular Optic System (MOS) to simplify mounting of popular optics without costly custom machining of the pistol's slide. The MOS is offered with cover plate when no optic is mounted and four plates options to comply with the specifications of some of the most trusted optic manufacturers in the industry. MOS gives you the option of adding tall iron sights allowing the optic and the iron sights to co-witness. This pistol does not include the modular sight, just the bracket to mount it on.