The Luth-Ar LUTH AR 223 RFL/FXD BFR TUBE ASSY is a complete buffer tube assembly kit designed to support a new .223 AR-15 rifle build or to convert your current AR-15 carbine to a A2 rifle-length recoil system. This rifle-length kit features a 6061-T6 aluminum A2 rifle buttstock extension tube finished in hardcoat anodized black, paired with a standard .223 rifle buttstock buffer spring and a standard rifle buffer body assembly for reliable cycling. Built for AR-15 compatibility, this complete buffer tube assembly is fixed in description, aligned with the Stocks & Buffer Tubes subcategory, and includes buffer, buffer tube, and spring as integral components. While converting a carbine length gas system to an A2 rifle-length buffer system can impact reliability, the kit provides the essential parts for a proper, secure fit and straightforward installation on compatible builds. Ideal for enthusiasts seeking a sturdy, purpose-built solution from a recognized name in rifle parts, the kit leverages the BAP-1 designation to denote its rifle-length, fixed buffer tube configuration and compatibility with standard AR-15 platforms, yielding a practical upgrade or build path for dependable gas system performance.