Upgrade the barrel on your 9mm AR build with the Modern Series EPC 9mm Straight Profile AR-15 Barrel from Ballistic Advantage. This 9mm barrel measures 11" and has a 1/2x28 thread pitch for adding your favorite muzzle devices. It is machined from 4150 Chrome Moly Vanadium steel with a QPQ finish and is compatible with standard mil-spec upper receivers and other 9mm dedicated uppers. Since it is 9mm on an AR-15 platform, it doesn't require a gas block or gas tube because it operates by blowback. This model features an integrated feed ramp and barrel extension.Features: Compatible with Colt/RR and GLOCK style AR builds Fits standard mil-spec uppers dedicated to 9mm 9mm caliber 11" barrel length, straight profile 1/2x28 thread pitch Machined from 4150 Chrome Moly Vanadium steel QPQ finish for corrosion resistance Integrated enhanced feed ramp and barrel extension Requires unique magwell conversion (Colt or RR style) with UZI mags OR dedicated 9mm lower with GLOCK magazines