Brand new, unfired 18" fluted 22 ARC AR-15 barrel. KAK industry, 416R stainless, bead-blasted matte grey finish, 1:7 twist, HBAR, straight flutes, threaded 1/2-28. Includes new rifle length gas tube (installed) with a new Aero Precision adjustable gas block (.750) (just hand tightened on barrel). Barrel is factory dimpled. Also includes a KAK Industry Big Hole muzzle device. (needs crush washer to time).