M and P Accessories AR-15 Customizable Lower Parts Kit ITAR is the perfect choice if you want to build a custom AR-15. This kit provides all the minor parts generally used in an AR-15 build, but allows the flexibility to add popular common after-market upgrades. Includes: Bolt Catch, Bolt Catch Plunger, Bolt Catch Roll Pin, Bolt Catch Spring, Buffer Retainer, Buffer Retainer Spring, Hammer Pin, Magazine Catch, Magazine Catch Button, Magazine Catch Spring, Pivot Pin, Pivot Pin Detent, Pivot Pin Detent Spring, Selector, Selector Detent, Selector Detent Spring, Takedown Pin, Takedown Pin Detent, Takedown Pin Detent Spring, Trigger Pin. Provides all the minor parts generally used in an AR-15 build Allows the flexibility to add popular common after-market upgrades Perfect choice if you want to build a custom AR-15