Product Description The Aero Precision AR-15 Complete Upper (APAR505611) is the same upper receiver assembly found in the Aero Precision M16A4 Special Edition Complete Rifle, bringing military-inspired performance to your build. Chambered in 5.56 NATO with a 20-inch barrel, this complete upper delivers reliable, full-rifle-length accuracy and the classic A2 aesthetic that serious shooters appreciate. The barrel is manufactured from 4150 Chrome Moly Vanadium steel with a QPQ corrosion-resistant finish and a 1:7 twist rate for outstanding bullet stabilization across a wide range of projectile weights. An A2 Detachable Carry Handle and a pinned A2 Front Sight Block with bayonet lug round out the traditional configuration, while a rifle-length gas system and standard A2 flash hider complete the package. Note: this complete upper does not include a Bolt Carrier Group (BCG) or Charging Handle. Product Highlights Classic M16A4-Style Configuration: Replicates the upper receiver assembly used in the Aero Precision M16A4 Special Edition Complete Rifle for proven military-grade performance. 20-Inch 5.56 NATO Barrel: 4150 Chrome Moly Vanadium construction with a QPQ corrosion-resistant finish and 1:7 twist rate for exceptional durability and accuracy. A2 Iron Sight Package: Includes a detachable A2 carry handle rear sight and a pinned A2 Front Sight Block with bayonet lug for traditional, battle-proven sighting. Rifle-Length Gas System: Provides a smoother, more consistent cycling experience with reduced felt recoil compared to shorter gas systems. Anodized Black Finish: Hard-coat anodized finish on the Standard M4 upper receiver delivers a durable, corrosion-resistant matte black appearance. Specs Brand: Aero Precision Manufacturer Part Number (MPN): APAR505611 UPC: 815421022285 Caliber: 5.56x45 NATO / .223 Remington Barrel Length: 20 inches Barrel Twist Rate: 1:7 Barrel Material: 4150 Chrome Moly Vanadium Barrel Finish: QPQ Corrosion Resistant Upper Receiver: Standard M4 Upper Receiver Handguard: A2 Style, Rifle Length Gas System: Rifle Length Sights: A2 Detachable Carry Handle and A2 Front Sight Block with Bayonet Lug Muzzle Device: Standard A2 Flash Hider Finish: Anodized Black Firearm Fit: AR-15 BCG / Charging Handle Included: No Country of Manufacture: United States Condition: New Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer. ]]>