Upgrade the performance of your AR15 build with this 6.5 Grendel Complete Upper Receiver. Designed to be a low recoil/high accuracy cartridge, the 6.5 Grendel is ideal for those looking to stretch the legs of their AR15 rifle, with proven results at 1000+ yards.Features:M4E1 Threaded Upper Receiver Features:New enhanced forging that gives the upper receiver a "billet look"New picatinny profile that blends seamlessly with our Enhanced Series HandguardsM4 Feedramps.250 takedown pin holesLaser engraved T-marksATLAS S-ONE Handguard Features:Front and rear picatinny railEliminated center of top rail for weight reductionIndexing grooves in 12:00 position for positive grip controlQuick disconnect sling socket at the 3, 6 and 9 o'clock positionsCompatible with low profile gas blocksCompatible with mil-spec AR15 upper receivers and barrelsSpecifications:Manufacturer: Aero PrecisionCartridge: 6.5mm GrendelOverall Length: 30 inBarrel Length: 20 inBarrel Profile: M4Gas System Length: Rifle LengthBarrel Twist Rate: 1-8Threads per Inch: 5/8x24Handguard Type: Free-FloatMuzzle Device: A2 Flash HiderGun Model: AR-15Condition: NewFabric/Material: 416R Stainless SteelAttachment/Mount Type: PicatinnyGas Block Journal Size-Diameter: .750 inGun Rail: PicatinnyGun Make: AR PlatformIncluded Accessories: NoneBolt Carrier Group Included: NoCharging Handle Included: NoWeight: 70 oz