5.56mm NATO 20" replacement barrel, 1:7 twist, 41V50 Mil spec vanadium alloy steel, fully machined and assembled with M4 extension, chromed bore and chamber for optimum performance and durability, .750" gas block, designed for rifle length gas system, drilled gas port, parkerized finish, muzzle thread 1/2 x 28. A2 fore end AR15 delta ring, assembly, snap ring and weld spring. A2 flash hider with crush washer. Rifle lenght gas tube with roll pin. Aero Prescision stripped A2 upper. Upper parts kit. Forward assist and dust cover. SAA Frankenbolt BCG .223/5.56 (Nickel Boron) Front sight post (square), detent and spring. A2 front sight tool. Riverman Gun Works charging handle. 10 rounds fired to zero. $500 Please text for more info. 425 760 2653 Thanks.