You can assemble a fine .308 Carbine with this Barrel Kit. It includes our medium profile 16.5” .308 Caliber Windham Weaponry Barrel; Mid Length Heat shielded Handguards; .308 A2 Type Birdcage Flash Hider with Crush Washer; Mid-Length Gas Tube; Gas Tube Roll Pin; Barrel Nut; Round Handguard Cap and .308 Delta Ring Components. This accurate and durable barrel is machined from 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 threaded 5/8” x 24 T.P.I. (threads per inch) and the Picatinny Rail Gas Block is taper pinned on to the barrel. The bottom of the gas block is threaded for a Q.D. sling swivel stud. All parts are highest quality, and made in the USA.