This kit features all of the Seekins Precision manufactured lower receiver parts as well as the pins and springs needed for assembly of your AR15 lower receiver. Included: Enhanced Bolt CatchBolt Catch Roll PinBolt Catch SpringBolt Catch PlungerBuffer Retainer PinBuffer Retainer SpringMag Release ButtonMag CatchMag Catch SpringSafety Selector Barrel 60/90 DegreeShort Safety Selector LeverLong Safety Selector LeverSelector DetentSelector SpringTrigger GuardTrigger Guard Roll PinSeekins Precision Takedown Pins (2) pivot and rear *Only available in builders kitTakedown Pin Detent (2)Takedown Pin Spring (2)Set Screw HexSHCS Hex (2) Seekins Precision Enhanced Builder's Kit 0011510063-F