Stern def.Trigger h2s 2 stage drop in ar-15 designed for pcc FEATURES:Standard mil-spec pin size Use for AR15 and AR106061 billet housingTrigger and disconnect machined from A2 tool steel bar stockHammer machined from S7 shock resistant steel bar stockSemi flat trigger bowCold Nitride Finish Other Features: 2 stage drop-in trigger, smooth 2lb first stage, positive 4lb second stage, semi flat tigger bow