Geissele 08-548S Super Duty MOD1 5.56 NATO 16" 1:7" CHF Chrome Lined Bbl DDC Complete Upper Receiver GroupThe Geissele Super Duty MOD1 5.56 NATO 16" 1:7" CHF Chrome Lined Bbl DDC Complete Upper Receiver Group 08-548S is a fully assembled upper receiver group designed for AR-15 style rifles. Geissele 08-548S features a 16-inch Cold Hammer Forged (CHF) chrome-lined barrel with a 1:7" twist rate, optimized for shooting 5.56 NATO ammunition. The upper receiver group includes all necessary components such as the barrel, handguard, gas block, and charging handle, providing a convenient solution for upgrading or building an AR-15 rifle. Additionally, the "DDC" likely refers to a Desert Dirt Color finish, providing a distinctive look. Overall, this upper receiver group offers high-quality construction and compatibility with AR-15 platforms for reliable performance..yellow-box p {font-size:16px}.special-tab {color: #FFFFFF}.yellow-box ul li {font-size: 16px;}The Geissele Super Duty MOD1 Complete Upper Receiver offers top-tier components for a custom AR build. Geissele Super Duty MOD1 Upper Receiver is precision-machined, cold hammer forged barrel is made from high-quality steel, coated with manganese phosphate and chrome lining for durability against the elements. The HUXWRX Flash Hider-QD 556 muzzle device enhances performance and is suppressor-ready. The included Reliability Enhanced Bolt Carrier Group features Nanoweapon coating, properly staked gas key, and a cam pin machined from H13 tool steel for corrosion and wear resistance. Extended upper rails improve stability and feeding reliability, while the Stressproof Bolt offers superior strength and fatigue resistance. The updated MK16 Super Modular Rail ensures a secure fit for a variety of optics, including iron sights, red dots, scopes, and thermal/night vision devices. Features of the Geissele Super Duty MOD1 Upper ReceiverPrecision machined, cold hammer forged barrelHUXWRX Flash Hider-QD 556 muzzle deviceGeissele own Reliability Enhanced Bolt Carrier GroupGeissele Stressproof BoltAirborne Charging HandleUpdated MK16 Super Modular Geissele Super Duty MOD1 5.56 NATO 16" 1:7" CHF Chrome Lined Bbl DDC Complete Upper Receiver Group 08-548S