The Wilson Combat TRTTU exemplifies the synthesis of rigorous testing and bulletproof design, serving as a new benchmark for drop-in AR triggers. This single-stage Tactical Trigger Unit (TTU) can be conveniently installed by users in any AR pattern rifle within a minute. The distinguished engineering of Wilson Combat allows for a resilient, ultra-crisp 4 lb. trigger pull that does not require fine tuning or adjustments. The device\'s reduced, positive trigger reset ensures quick successive on-target shots.Featuring unique hammer geometry, the TTU supports reliable ignition with a wide variety of military and surplus ammunition. Its 1911-style half-cock notch further qualifies it to meet or exceed military specifications for drop safety. The TTU comes as a pre-assembled, CNC-machined trigger housing composed of an H13 heat-treated trigger, hammer, sear, and a stainless steel spring, to simplify installation.Wilson Combat\'s AR-15 Tactical Trigger Units function reliably in any standard Usgi style AR-style lower receiver with standard GI trigger pins of .154\" diameter, irrespective of the caliber, including 7.62/.308 length AR receivers. Note: The TTU can be installed in the S&W MP-10 .308 AR; however, the rifle\'s ambidextrous bolt catch must be removed first.