This complete upper includes our new ATLAS R-ONE Handguard! The R-ONE handguards are designed with size and weight in mind, while still providing plenty of real-estate to accommodate any attachment needs the end user may have. Our proprietary ATLAS attachment system is a durable and dependable mounting platform, maintaining a slim profile while still providing the strength and stability customers have grown to love from Aero Precision handguards.WARNING: California`s Proposition 65Features:Enhanced forging that gives the upper receiver a "billet look".Picatinny profile that blends seamlessly with our Enhanced Series Handguards..250 takedown pin holes.Laser engraved T-marks.Includes port door and forward assist installed.Full top picatinny rail for optional attachments.Quick disconnect sling socket at the 3, 6 and 9 o'clock positions.Compatible with low profile gas blocks.Compatible with mil-spec AR15 upper receivers and barrels.Specifications:Manufacturer: Aero PrecisionCartridge: .300 AAC BlackoutBarrel Length: 10 inGas System Length: Pistol LengthBarrel Twist Rate: 1-7Threads per Inch: 5/8x24Muzzle Device: A2 Flash HiderGun Model: AR-15Condition: NewFabric/Material: Chrome Moly VanadiumGas Block Journal Size-Diameter: .750 inHandguard Length: 9 inGun Make: AR PlatformWeight: 21 oz