The AM-15 Pistol Lower Build Kit Includes all the following parts to complete your lower receiver build: Lower Parts Kit Black; AM-15 Buffer Tube Pistol Length; AM-15 Buffer Tube Castle Nut; AM-15 Buffer, Carbine Length; AM-15 Buffer Spring Carbine Length; AM-15 Receiver End Plate Ambi The Lower Parts Kit for AM-15 includes the following: Bolt Catch, Bolt Catch Plunger, Bolt Catch Roll Pin, Bolt Catch Spring, Buffer, Retainer, Buffer Retainer Spring, Disconnect, Disconnect Spring, Traditional Hammer (Black in Color), Hammer Pin, Hammer Spring, Magazine Catch, Magazine Catch Button, Magazine Catch Spring, Pistol Grip (A2 style), Pistol Grip Lock Washer, Pistol Grip Screw, Pivot Pin, Pivot Pin Detent, Pivot Pin Detent Spring, Selector, Selector Detent, Selector Detent Spring, Takedown Pin, Takedown Pin Detent, Takedown Pin, Detent Spring, Traditional Trigger (Black in Color), Trigger Guard, Trigger Guard Roll Pin, Trigger Pin, Trigger Spring. The Pistol Buffer Tube comes Anodized Black and is Compatible with AR-15 Platform. The buffer tube castle nut is the standard AR-15 buffer tube nut. The Carbine Length, Standard Buffer is Compatible with AR-15 Platform. The Carbine Length Buffer Spring, is the Music Wire type and it is Compatible with AR-15 Platform. The Am-15 Mil Spec, Ambidextrous Receiver End Plate has two Sling Holes and comes with a Parkerized Finish.