The Geissele Automatics Tactical Super Semi-Automatic Trigger is a semi-automatic, non-adjustable two stage trigger and is safety certified by the Crane Naval Surface Warfare Center. These Rifle Triggers by Geissele provide accurate trigger control for long shots and close combat. The Geissele Super Semi-Automatic Precision Trigger is perfect for hunting, law enforcement, and home defense. Please note, these triggers are designed for mil-spec AR15/M4 carbine rifles. AR15 triggers are not compatible with the Sig MPX/MCX weapons or Pistol Caliber Carbine AR15/M4 variants. Using them in these platforms will void the warranty. Specifications for Geissele Super Semi-Automatic AR-10/AR-15 Trigger: Manufacturer: Geissele Color: Black Trigger Shape: Curved Trigger Pull Weight: 4.5 lb Trigger Pin Size: Mil-Spec Hand: Ambidextrous Gun Make: AR Platform Gun Model: AR-10, AR-15 Gun Type: Rifle Included Accessories: Standard Condition: New Features of Geissele AR-10/AR-15 Super Semi-Automatic (SSA) Trigger: Sear surfaces are cut by a wire edm machine; A full force hammer spring is used for quick locktime and positive ignition of all types of ammo; There are no adjustment screws to come loose; All springs are captive; The entire trigger can be dissembled for cleaning; The trigger can be installed without removing the safety; Sear engagement is pre-set from the factory; NOTE: The Geissele SSA does not fit HK416 weapons with firing pin safety Package Contents: Geissele AR-10/AR-15 Super Semi-Automatic (SSA) Trigger