The Geissele Automatics Super Semi-Automatic AR-15 Enhanced Trigger is a non-adjustable, two-stage trigger that provides improved trigger control and accuracy while reducing the first and second-stage pull weights. These finely-tuned Rifle Triggers by Geissele a Standard Mil-Spec pin and are made from quality tool steel. The Geissele Super Semi-Automatic Enhanced Precision Trigger is easy to install with safety on and disassembles for cleaning. When you need a reliable trigger, the Geissele Automatics Super Semi-Automatic AR-15 Enhanced Trigger is perfect. 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 Automatics Super Semi-Automatic AR-15 Enhanced Trigger: Manufacturer: Geissele Color: Black Trigger Shape: Curved Trigger Pull Weight: 3.5 lb Trigger Pin Size: Mil-Spec Hand: Ambidextrous Gun Make: AR Platform Gun Model: AR-10, M4, AR-15 Gun Type: Rifle Included Accessories: Standard Condition: New Features of Geissele Automatics Super Semi-Automatic AR-15 Enhanced 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-E does not fit HK416 weapons with firing pin safety Package Contents: Geissele Automatics Super Semi-Automatic AR-15 Enhanced Trigger