CMC's innovative self-contained and easy-to-install AR-15 trigger groups have been completely re-tooled to maximize production capacities incorporate new design enhancements and reduce cost. CMC's AR-15 trigger groups have always yielded exceptional trigger pull dynamics for our tens of thousands of satisfied customers.Features: Single Stage Trigger 3.5lb pull weight Small pin Ultra-crisp trigger with no feel of creep prior to hammer release The trigger has a glass-smooth break with no feel of grittiness Minimal lock time is designed into the assembly using controlled hammer weight and balance activated by a rocket wire hammer spring assuring repeatable function with either commercial or military grade ammunition Trigger pull is factory pre-set and not user adjustable Positive trigger reset allows a quick follow up shot on target Hand assembled and hand tested Totally self-contained one-piece assembly Comes with CMC Anti-Walk Pin Set Fits MIL-SPEC AR-15 and AR-10 style rifles Made from 8620 Alloy Steel and S7 Tool Steel with machined tolerances of +/- .001a ^2 Easy to install