Brownells Hammer/Trigger Pin Set Features The Brownells Colt AR-15 .172 inch Large Hammer/Trigger Pin Set works together with the Brownells Hammer/Sear Block which holds the hammer and sear outside of the firearm during fitting and inspection. This setup exposes the exact engagement point between the two parts an area that is nearly impossible to view clearly once the components are installed in an assembled lower. An Allen screw locks the pin in place once positioned ensuring the hammer and sear are held exactly as they would be relative to their true location in the firearm. This level of control is important when cutting or adjusting engagement surfaces since small changes there directly affect trigger pull and reliability. Each pin in the set is individually numbered for easy identification which helps keep track of parts during a fitting session involving multiple components. This numbering system is especially useful when comparing factory parts against aftermarket replacements side by side. Sized for larger .172 inch pin AR-15 pattern trigger groups the set gives accurate fitment for platforms using this pin diameter. Gunsmiths who regularly perform trigger and hammer work on AR-15 rifles will find this pin set a valuable precise addition to their bench. Brownells Colt AR-15 .172 Large Hammer/Trigger Pin Set Specifications Brand: Brownells Model: .172 Hammer/Trigger Pin Set Compatible Hosts: AR-15 Available At: GrabAGun