This 20" AR-STONER(TM) LR-308 Barrel is perfect for use in competition or hunting where both accuracy and reliable function are important factors. Chambered in .308 Winchester and manufactured from 4150 Chrome Moly Vanadium Steel, this 1 in 10" twist, heavy contour barrel gives you high quality at a great value. Additional features include a rifle-length gas system, AR-10 feed ramps and 5/8"-24 threaded muzzle. The barrel extension and locator pin are both included and installed at the factory.