longer slide adds 1 inch of length when compared to the gx4increasing muzzle velocity and sight radius making it easier to maintain accuracy.Standard backstrap profile features a slight palm swell.Those who favor a higher wrist position for natural point-of-aim can install the included high-swell backstrap.Direct thread no plate system accommodates todays most popular red dot optics including: shield rmsc holosun hs507k x2 sightmark mini shot a-spec m3 trijicon rmr cc red dot (with adapter plate p/n: 10028170 a blackout steel serrated drift adjustable rear sight and fixed (white dot) front sight promote fast target acquisition when not running a red dot.Delivers accuracy and predictability courtesy of its crisp precise sear break and the pleasingly short and tactile reset that is fundamental to quick on-target follow-up shots.Frame Finish: BlackAction: Striker FireCaliber: 9mm LugerBarrel Length: 3.70"Capacity: 10+1Safety: Loaded Chamber Indicator Manual TriggerGrips: Black PolymerSight Configuration: Fixed Front Adjustable Rear