Faxon Firearms AR15 5.56 NATO Threaded Barrel 10.5in Pencil Profile Carbine-Length 1-8 Twist 1/2x28 Black. 625in gas block included for maximum reliability in a lightweight Pencil profile. The Faxon 10.5in Pencil Profile Barrel with Pinned Gas Block combines Faxon's lightweight contour with a factory-installed pre-drilled gas block and pin-saving time effort and ensuring long-term reliability. The gas block is pre-notched and pre-aligned in-house for a perfect fit every time. Built from 4150 CMV steel and finished inside and out in black nitride this Pencil contour barrel keeps weight to a minimum while maintaining accuracy and rigidity. Ideal for compact maneuverable builds this carbine-length barrel is stress relieved air-gauge tested MPI inspected and headspace verified for duty-grade performance. Specifications for Faxon Firearms AR-15 5.56 NATO Gas Block Pencil Profile 10.5in Carbine-Length Threaded Barrels: Manufacturer: Faxon Firearms Color: Black Nitride Finish: Nitride Fabric/Material: 4150 CMV Caliber: 5.56x45mm NATO Barrel Length: 10.5 in Barrel Profile: Pencil Gas System Length: Carbine Length Gas Block Journal Size-Diameter: .625 in Barrel Twist Rate: 1-8 Barrel Material: 4150 Chrome Moly Vanadium Flutes: No Gun Make: AR Platform Gun Model: AR-15 Included Accessories: Pinned 3 Port Brake Condition: New Gas Block Journal Size-Length: 1.1 in Gun Type: Rifle Firearms Threads Per Inch: 1/2x28 Rifling Profile: Button Rifling Features of Faxon Firearms AR-15 5.56 NATO Gas Block Pencil Profile 10.5in Carbine-Length Threaded Barrels: Factory-pinned .625in gas block: Precision aligned and installed for secure operation. Ultra-lightweight Pencil profile: Minimizes front-end weight for fast handling and reduced fatigue. Carbine-length gas system: Reliable performance with both unsuppressed and suppressed setups. Durable nitride finish: Resists wear corrosion and fouling for long-term use. Rigorous QC: Stress relieved air-gauge tested MPI-inspected and headspace verified in-house by Faxon Firearms. Package Contents: Faxon Firearms AR-15 5.56 NATO Gas Block Pencil Profile 10.5in Carbine-Length Threaded Barrels What firearm models does the manufacturer say Faxon Firearms AR-15 5.56 NATO Gas Block Pencil Profile 10.5in Carbine-Length Threaded Barrels is compatible with? The manufacturer says that Faxon Firearms AR-15 5.56 NATO Gas Block Pencil Profile 10.5in Carbine-Length Threaded Barrels is compatible with AR-15Faxon Firearms 15A58C10NPQ-APGB: 14.5in Pencil Profile AR15 Barrel 556 Nato w/ Pinned 3 Port Brake