This complete .308 Caliber Windham Weaponry Flattop Upper Receiver Assembly is ready to snap onto your Windham Weaponry .308 Lower and take to the range. It features a Magpul MOE M-Lok Rifle Length Forend on its 20” Medium Profile Fluted Barrel. This highly accurate Barrel is 4150M Chrome Moly Vanadium 11595E Steel, Chrome Lined in Bore and Chamber, rifled 1 turn in 10 inches – 6 lands & grooves – right hand twist. The muzzle is fitted with an A2 type .308 Flash Suppressor. A mounting stud for a Q.D. Sling Swivel is fitted to the Picatinny Rail Gas Block – which is on the same plane as the flat top type Upper Receiver’s MIL-STD 1913 Top Rail. The Upper Receiver is CNC machined from 7075T6 aircraft grade aluminum, hard coat black anodized to mil spec.