Strike Industries AR Trigger Hammer Jig - This easy to use apparatus allows full assembly and testing of any AR-15 trigger set up prior to installation on your rifle. The AR-15 Trigger Jig allows you to clearly see the sear, hammer, and disconnector engagement points while under normal spring tension. The Trigger Jig enables you to dry fire the trigger without damaging the jig or other internal parts and make necessary adjustments while checking functionality. It also allows you to mount the jig in a vise and adjust for trigger pull without having the rifle present. Practice Installing The Trigger Without Taking A Chance At Scratching Your Rifle Clear Visibility To See All The Moving Parts Of The Trigger While In Motion Allows You To Demonstrate How The Trigger Works You Can Also Install Selector Switch And Pistol Grip Hammer Bumper