Self-contained module is ready to install in your small-pin AR and deliver an exceptionally smooth, crisp, creep-free single-stage trigger pull that feels more like a traditional bolt action than a combat rifle trigger. 100% drop-in-no gunsmithing, fitting, or adjusting required. All components are captive in the lightweight, aluminum alloy housing. Hammer is wire-EDM machined from S7 tool steel that combines hardness to resist wear with superior impact resistance to withstand heavy use without chipping or breaking. Other components are EDM cut from A2 tool steel, then heat treated to Rc 56-60 for long service life. Precision-ground engagement surfaces ensure superb reliability and a crisp, clean hammer release. Installs using your rifle's original hammer/trigger pins; proprietary design eliminates pin walkout. Features: Drop-In Design Yellow Aluminum Housing Single Stage Trigger Type Curved Trigger Profile Trigger Pull Weight: 3 lbs (default), 4 lbs, or 4.5 lbs Settings Steel Hammer .154" Pin Diameter