The Armaspec SMB Buffer Kit H3 Gen 3 provides everything needed to complete your AR-15 rifle build with advanced Sound Mitigation Buffer (SMB) technology that offers superior performance over standard mil-spec buffer springs and weights.SMB Buffer Kit H3 Gen 3 Complete AssemblySound Mitigation Buffer (SMB) technologyIncludes SMB Buffer Buffer Tube Endplate and Castle NutFits AR-15 Pattern FirearmsSuperior upgrade from OEM mil-spec componentsThis complete buffer tube assembly is designed for AR-15 enthusiasts seeking enhanced performance and reduced felt recoil through innovative sound mitigation technology.