Product DescriptionComplete your AR-15 lower group with the CMMG A1-style fixed stock and rifle receiver extension kit. Designed to pair with your preferred lower parts kit, this complete assembly includes the rifle-length receiver extension tube along with the buffer and action spring needed for a classic A1-style fixed-stock setup. It also includes the end cap and stock screw to help streamline installation.Product HighlightsComplete A1-style fixed buttstock and rifle receiver extension kit for AR-15 lower buildsIncludes rifle-length receiver extension tube, buffer, and rifle action springIncludes end cap and stock screw for a more complete installation packageMil-Spec buffer tube sizing for compatibility with Mil-Spec AR-15 receiver extensionsDurable mixed-material construction (aluminum and polymer) for dependable useSpecsBrand: CMMGManufacturer Part Number: 55CA646UPC: 815835012636Platform Fit: AR-15 / AR riflesStock Style: A1 length fixed stockIncluded Components: Receiver extension tube, end cap, recoil spring (action spring), buffer, stock, stock screwBuffer Tube Size: Mil-SpecOverall Length: 15 inMaterial: Aluminum, PolymerColor/Finish: BlackWeight: 2 lbCondition: NewDisclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product's manufacturer.