Dark Storm Industries AR-15 5.56x45mm NATO Threaded AR Barrel 12.5inch SOCOM Carbine Length 1-7 Twist Nitride Black. Made from rugged steel this barrel is ideal for AR-15 pistol builds and tactical applications. Specifications for Dark Storm Industries AR-15 5.56x45mm NATO Threaded AR Barrel: Manufacturer: Dark Storm Industries Color: Black Finish: Nitride Caliber: 5.56x45mm NATO Barrel Profile: SOCOM Gas Block Journal Size-Diameter: .750 in Barrel Twist Rate: 1-7 Barrel Material: Steel Flutes: No Gun Make: AR Platform Gun Model: AR-15 Firearms Threads Per Inch: 1/2x28 Package Contents: Dark Storm Industries AR-15 5.56x45mm NATO Threaded AR Barrel What firearm models does the manufacturer say Dark Storm Industries AR-15 5.56x45mm NATO Threaded AR Barrel is compatible with? The manufacturer says that Dark Storm Industries AR-15 5.56x45mm NATO Threaded AR Barrel is compatible with AR-15Dark Storm Industries DSI-BRL-556SC-12C7T-NIT: AR-15 5.56x45mm NATO Threaded AR Barrel 12.5inch SOCOM Carbine Length 1-7 Twist Nitride Black