This genuine Colt 11.5" Heavy Profile Barrel epitomizes modern warfare’s need for speed and mobility - AND it’s ready to install on your next AR-15 pistol or SBR.  The barrels is forged from ordnance-grade carbon steel, with a chrome-lined bore and chamber, plus a traditional matte black Parkerized finish. The Colt 11.5" Heavy Profile Barrel comes with the barrel extension, M4-type (round) front handguard cap, and front sight tower/gas block ALL installed. The gas port is drilled for a carbine-length gas tube - giving you an extra measure of reliability in a pistol build. 1-7" rifling twist 1/2"-28 tpi muzzle threads Front sight tower/gas block has bayonet lug Front sight post IS included Carbine-length gas tube not included OAL of entire assembly: 12-1/8" All NFA rules apply Built with compatibility in mind, Colt’s 11.5" Heavy Profile Barrel fits any standard "mil-spec" AR-15 / M16 / M4 upper receiver, and it’s chambered for 5.56x45mm NATO, so it will also safely fire civilian .223 Remington ammo as well.