Caliber: 5.56mm NATO. Capacity: 30-round magazine. Barrel: 16″ cold hammer-forged chrome-lined, 1:7 twist, free-floated inside M-LOK URX handguard. Stock: Magpul MOE. Sights: Post front, fully adjustable rear (300-meter sight). Features: URX-4 upper receiver; two-stage trigger, 30-round magazine. Black finish. Weight: 6.55 lbs. Length: 33.5” to 36.5”. Made in USA by Knight's Armament Co.