Daniel Defense's Semiautomatic Parts Kit was designed for those who are interested in assembling their own AR-15. Each part is MIL-SPEC and is of the highest quality. This Kit Includes: Semi-Auto disconnectorDisconnector springBuffer retaining pinHammer springHammer with J-pinTrigger springSemi-auto triggerAmbidextrous selector kitSpring pin slotted bolt catchBolt catchBolt catch plungerBolt catch springMagazine catchTakedown pinTrigger/Hammer pin (x2)Magazine release buttonMagazine catch/release springPivot pinDetent takedown/pivot pin (x2)Takedown/pivot pin spring (x2)Selector detentSelector detent springPistol gripTrigger guardSocket set cup screwTrigger guard Spring pinPistol grip lock washerPistol grip slot screwPistol grip cap Daniel Defense Semi-Auto Lower Receiver Parts Kit 05-013-21007