Includes: M2 tool steel ARC Cam M2 tool steel ARC Lever M2 tool steel ARC Detent Bar 4140 steel ARC Primary Selector 4140 steel ARC Ambi Selector Cam, Lever, and Detent Bar feature DLC coating. Selector Levers feature Black Oxide coating. Includes pre-cut trigger and standard safety detent. Trigger Compatiblity: Most Mil-Spec Triggers w/ SS Cut Geissele Triggers w/ SS Cut* SSA SSA-E SSA-E X Trigger SSA-X SD-E SD3G SDC SSP S3G G2S ALG Triggers w/ SS Cut Defense QMS Defense ACT BCM PNT Trigger w/ SS Cut PSA Enhanced Polished Trigger (EPT) w/ SS Cut Aero Precision FCG w/ SS Cut CMMG FCG w/ SS Cut Known incompatible triggers: LaRue Tactical MBT-2S, CMC Single Stage Flat/Curved, Rise Armament RA-140