20-piece Lower Parts Kit with standard trigger pins and standard safety - Safety detent pin - Safety detent spring - Mag catch - Mag catch spring - Mag release button - Bolt catch - Bolt catch spring - Bolt catch plunger - Bolt catch roll pin - Pivot pin - Takedown pin - Pivot/takedown spring (2 pcs) - Pivot/takedown detent (2 pcs) - Buffer retention pin - Buffer retention spring - Standard trigger pins (2 pcs) - Standard safety selector - Does not include fire control group grip or trigger guard