Looking to complete an AR-15 lower receiver that you picked up and need a no-nonsense lower parts kit? The Rise Armament AR-15 Lower Parts Kit may be just what you need. This Lower Parts Kit includes the following components: 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 Please note that this Mfg: Rise Armament