Brownells Modern Series 16" 5.56 M4 Carbine AR-15 Complete Upper

Includes:AR15 Assembled Upper Receiver16" 5.56 M4 Carbine Length Barrel, Modern SeriesFSB, Delta Ring Assembly, and Carbine Length Gas TubeProduct comes completely assembledThis complete upper does not include a BCG, Charging Handle, or Muzzle Device. These products may be selected as add-ons under the drop-down menusAll Parts Made in the USAAR15 Upper Features:Forged from 7075-T6 aluminumM4 Feedramps.250 takedown pin holesLaser engraved T-marksIncludes port door and forward assist16" 5.56 M4 Government Carbine Length Barrel, Modern Series Features:Twist: 1:7 inchesThreading: 1/2X28Material: CrMoVFinish: QPQGas Block Journal: .750Gas System Length: Carbine Length