Upgrade your AR-15 build with the reliable Aero Precision AR-15 Mil-Spec Carbine Receiver Extension / Buffer Tube in Black Anodized finish. Crafted for precision and durability, this essential component ensures smooth operation and compatibility with a wide range of stocks, making it a must-have for enthusiasts seeking mil-spec performance without compromise. Key Features Mil-Spec Dimensions: Precisely machined to military specifications for seamless integration with standard AR-15 components, preventing compatibility issues common in mismatched builds.