CMC's self-contained, drop-in trigger module replaces the heavy factory trigger found in many commercial AR-15s and delivers a crisp, clean pull with a consistent, pre-set pull weight. Originally designed by competition shooter Chip McCormick to provide all the advantages of a fine, match-grade, single-stage trigger without having to fit and adjust multiple components. A rigid, steel, trigger housing holds all the factory-tuned internal components in proper alignment for easy, fast installation. Generous, precision-ground sear/hammer engagement surfaces provide a remarkably clean, crisp release while preserving reliable function. Each trigger assembly is tweaked at the factory Mfg: Cmc Triggers SPECS: Hammer/Trigger - Steel, blued finish. Housing - Steel, in-the-white. Fixed pull weight is not user-adjustable. Includes two (2) Chicago-style center pins. Fits AR-15 (or AR-308 that uses AR-15 trigger) with .154" diameter trigger and hammer pins.