The CMC Tactical Trigger Group is a fully self contained, 100% drop-in fire control group upgrade for M4, AR-15, LR-308 and AR-10 rifles. The CMC has been improved beyond the original Super Match trigger design, the double patented Tactical Trigger design offers truly remarkable and unprecedented trigger control, trigger feel and accuracy, while also the keeping the rugged reliability of a Mil-Spec factory trigger group. Trigger pull is factory pre-set at 3-1/2 to 4 pounds and is not user adjustable. Fits most standard Mil-Spec lower receivers with .154" trigger and hammer pin holes.