We’ve added the excellent Midwest Industries K-Series Key Mod 15” Handguard to this .308 Caliber Windham Weaponry Flattop Upper Receiver Assembly. The complete Assembly includes an 18” Medium Profile Fluted Barrel in .308 Caliber complete with .308 Bolt and Bolt Carrier. The Barrel is 4150M Chrome Moly Vanadium 11595E Steel, Chrome Lined in Bore and Chamber, rifled 1 turn in 10 inches – right hand twist – with 6 lands & grooves. A Low Profile Gas Block is in place under the forend assembly, and the muzzle is fitted with an A2 Birdcage Type Flash Hider. The Midwest Industries Key Mod Handguard includes a 2” Key Mod Rail Section and a Push Button Q.D. Sling Swivel for use in any of the 5 sockets. The MIL-STD 1913 Top Rail is on the same plane as the Upper Receiver Rail, and is T-marked its entire length for accessory location. It is CNC machined from 6061 aircraft grade aluminum, hard coat anodized to mil spec and fully dehorned for a smooth, comfortable feel over its slim 1.5” outside diameter.