The Single-Stage CMC Trigger Group is a completely self contained, 100% drop-in, fire control group upgrade for the AR-15, and AR-10 family of rifles; Trigger pull is factory pre-set, is not user adjustable and comes in 3.5 lb. trigger weights; The patented Flat Trigger design yields truly remarkable and unprecedented trigger control, trigger feel and accuracy; An ultra-crisp trigger with no feel of creep prior to hammer release; Trigger has a Glass-Smooth Break with no feel of grittiness; Trigger components are fabricated from 8620 alloy steel and S7 Tool steel, machined to exacting tolerances and finished for the longest service life possible; Minimal Lock-time is designed into the assembly using controlled hammer weight and balance and activated using a Rocket Wire hammer spring; Positive Trigger Reset allows a quick follow up shot on target; Trigger is easy to install following the included instructions