Caliber: 9mm. Capacity: 17-round magazine. Barrel: 3.9”. Grips: Textured polymer. Sights: Siglite front/night rear, optics-ready. Length: 7.2” overall. Weight: 28.1 oz. unloaded. Finish: Coyote tan. Features: Commercial version of U.S. Military M18, manual thumb safety. M17X and M18X have factory-mounted Romeo-X optics (add 120%).