The CMC AR-15/AR-10 9mm PCC Single Stage Drop-In Trigger is the same Flat Trigger Bow shape for your large caliber rifles can now be successfully installed in your pistol caliber carbine. Hammer dimensions have been modified to facilitate the 9mm platform. The Curved Trigger has a smooth feel and ultra-clean break. Features- multiple trigger pull weights minimal lock time controlled hammer weight and balance activated by a wire hammer spring assuring repeatable function with either commercial or military grade ammunition trigger pull is factory pre-set and not user adjustable and a positive trigger reset allows a quick follow up shot on target. Comes with CMC Anti-Walk Pin Set