Nickel boron finishTotal pull weight 4.0-4.5 lbsStage 1, 2.0-2.5Stage 2, 2.0-2.5Drop-In Two-Stage Target Trigger UpgradeCenturion Arms LLC Match Grade Competition Trigger Group gives you a smooth, consistent, two-stage pull, with a clean break and little-to-no pre- and over-travel. It's built with a fit, finish, and attention to detail found in very few AR triggers, let alone one at this price-point.Each Centurion Arms LLC Match Grade Competition Trigger Group is machined from hardened A2 tool steel (NOT MIM parts!) to precise dimensions, then micro polished to eliminate "creep" during the pull. Finally, the hammer and trigger in each Match Grade Competition Trigger Group gets an ultra-hard, self-lubricating Nickel Boron coating, to ensure an extremely smooth pull.Hardened A2 tool steel hammer, trigger, disconnectorUltra-hard Nickel Boron coating on hammer / triggerUltra-grade stainless steel music wire springs includedDrop-in fit in standard AR-15 lower receiverPins included (.153" dia.)Centurion Arms LLC Match Grade Competition Trigger Group has the two-stage pull preferred by precision rifle shooters. It gives you excellent control that lets you "stack" the trigger then pause before you completing the pull through the second stage.