Geissele Super Duty MOD1 5.56 NATO 16" 1:7" CHF Chrome Lined Barrel Black Complete Upper Receiver Group 08-548B delivers top-tier performance for tactical and competitive shooters who demand durability and precision. This complete upper features a 16-inch cold hammer-forged barrel with a 1:7 twist rate, enhanced by a chrome lining to increase barrel life and corrosion resistance. The barrel is finished in black and designed with the Geissele profile to provide an optimal balance of weight and strength. It comes equipped with a Geissele Reliability Enhanced Bolt Carrier Group coated with Nanoweapon and a chrome-lined gas key for smooth, reliable cycling and long-term durability. The assembly also includes an Airborne Charging Handle for improved ergonomics and consistent performance under demanding conditions. The black anodized upper receiver is paired with a MK16 Super Modular Rail handguard that offers extensive modularity for accessory attachment. This complete upper receiver group is built to deliver exceptional accuracy and rugged reliability, making it a solid choice for modern 5.56 NATO platforms. Caliber: 5.56 NATO Barrel Length: 16" Barrel Profile: Geissele Profile Barrel Construction: Cold Hammer Forged (CHF) Barrel Finish: Chrome Lined Barrel Twist Rate: 1:7 Bolt Carrier Group: Geissele Reliability Enhanced BCG (Nanoweapon-coated, Chrome-lined gas key) Charging Handle: Airborne Charging Handle Handguard: MK16 Super Modular Rail Receiver Finish: Black Anodized Part Number: 08-548B Geissele Automatics Geissele Super Duty MOD1 5.56 NATO 16" 1:7" CHF Chrome Lined Bbl Black Complete Upper Receiver Group 08-548B