The Luth-AR 24 inches Fluted Bull Barrel Complete Upper Barrel Assembly Starts with a 24 inches, .223 caliber fluted bull barrel made from 416 SST with a 1:9 inches twist mated to a A3 Flattop receiver which includes a bolt carrier, charging handle, forward assist and ejection port cover. The upper is then topped off with a low-profile gas system and an ergonomic 15 inches Palm Handguard with KeyMod slots and a Picatinny top-rail. Features: HG-V-15K - palm handguard - vented 15 inches KeyMod with barrel nut BL-B24FT - 24 inches bull barrel, fluted, threaded 416 stainless steel FTT-EA1 - A3 upper receiver assembled BC-A-223 - .223 fully assembled bolt carrier UR-19 - charging handle