Brownells AR-15 Rifle Receiver Extension Features The Brownells AR-15 Rifle Receiver Extension is machined from 7075 aluminum a high strength alloy commonly used in critical AR-15 components where weight and durability both matter. The matte black hardcoat anodized finish adds a hard wear resistant surface layer that stands up to repeated buttstock cycling and rough handling in the field. Its 9 5/8 inch length and 1.110 inch diameter are built to rifle length specifications ensuring correct buffer spring travel and reliable cycling. This dimensional accuracy is essential for proper function since an incorrectly sized extension tube can cause short-stroking or failure to lock back. Builders replacing a damaged or worn buffer tube or completing a new rifle length AR-15 build will find this extension a straightforward drop-in component. It fits standard AR-15 and M16 lower receivers along with rifle length buttstocks making it compatible with a wide range of common configurations. Because it ships as a single component it pairs naturally with a rifle length buffer and spring for a complete rebuild. Brownells backs the part with the fit and finish expected from a trusted name in AR-15 parts and accessories. Brownells AR-15 Rifle Receiver Extension Specifications Manufacturer: Brownells Model: AR-15 Rifle Receiver Extension Type: Buffer Tube Color: Black Material: Aluminum Length: 9.625 Diameter: 1.110 Compatible Hosts: AR-15 AR-308 Available At: GrabAGun