Spikes Tactical .308 Barrel Kit for AR-10 20 in 1-12 Twist w/Gas Block & Tube Black. 308 barrel gas block and gas tube. This kit was put together for the smoothest shooting .308 barrel you will ever install on your AR-10. Specifications for Spikes Tactical .308 Barrel Kit for AR-10 w/Gas Block & Tube: Manufacturer: Spikes Tactical Color: Black Finish: Black Nitride Fabric/Material: Stainless Steel Caliber: .308 Winchester Gas Block Journal Size-Diameter: .750 in Threads per Inch: 5/8x24 Barrel Twist Rate: 1-12 Gun Model: AR-10 Projectile Caliber: .308 Caliber Country of Origin: USA Features of Spikes Tactical .308 Barrel Kit for AR-10 w/Gas Block & Tube Chrome Lined Cold Hammer Forged 1/12 Twist Rate 5/8 X 24 Thread Pitch for Muzzle 7.62 Nato Chamber .750 Gas Block Seat M4 Style Ramped Barrel Extension MilSpec Phosphate Coating Heavy Profile Low Profile Gas Block Solid Billet Steel .750 I.D. Black Nitride Coating Proprietary Length Tube Mil-Spec 304 stainless steel Black Nitride Finish Stainless Steel Spring Pin Package Contents: Spikes Tactical .308 Barrel Kit for AR-10 w/Gas Block & Tube What firearm models does the manufacturer say Spikes Tactical .308 Barrel Kit for AR-10 w/Gas Block & Tube is compatible with? The manufacturer suggests that Spikes Tactical .308 Barrel Kit for AR-10 w/Gas Block & Tube is compatible with AR-10Spikes Tactical SBX2005-RLK: .308 Barrel Kit for AR-10 20 in 1:12 Twist w/Gas Block & Tube Black