Buttstock kit a high-quality, mil-spec assembly designed for durability and precision. Whether you're building a new rifle or enhancing an existing one, this kit provides everything you need for a solid, stable shooting experience. AR-15 rifle A2 buttstock kit for classic design and reliable performance Includes an AR-15 rifle spring, AR-15 rifle buffer, A2 extension tube, A2 spacer, assembly screw and a polymer stock with a storage compartment