USED Proof Research PR15 Carbon Fiber Barrel 6mm ARC 16 in Rifle Length 5/8x24 Thread 1-7.5 Twist 4 Groove Carbon Fiber. With a lightweight design that provides an optimal weight savings these AR15 Barrel by Proof Research are much more durable than their steel predecessors and deliver softer recoil - boosting your performance in the field backcountry or at the range. The high heat resistance of the aerospace-grade carbon fiber wrap inside the Proof Research PR15 6mm ARC Threaded Barrel ensures that your barrel doesn't overheat and delivers the durability you need to create powerful weapon modifications. A high temperature resistance also allows this barrel to work efficiently in hot or colder environments ensuring that you're using the Proof Research PR15 Carbon Fiber Barrel with ease. Specifications for Proof Research PR15 6mm ARC Carbon Fiber Threaded Barrel: Manufacturer: Proof Research Color: Graphite/Sliver Fabric/Material: Carbon Fiber Caliber: 6mm ARC Barrel Profile: Standard Gas Block Journal Size-Diameter: .750 in Barrel Twist Rate: 1-7.5 Flutes: No Gun Make: AR Platform Gun Model: AR-15 Gas System Type: Direct Impingement Firearms Threads Per Inch: 5/8x24 Features of Proof Research PR15 6mm ARC Carbon Fiber Threaded Barrel Lightweight: Up to 64percent lighter than traditional steel barrels of similar contour Extreme Temperature Resistance: Improved heat dissipation for cooler and longer lasting barrels Unprecedented durability: Wrapped with high-strength aerospace-grade carbon fiber impregnated with a proprietary matrix resin All barrels with Intermediate Rifle +1 Rifle +2 and Rifle +3 gas systems include the proper gas tube. Our AR-10 barrels use a deep feed system that makes the feed ramps compatible with the feed ramps in the lower receivers of both DPMS and Armalite style rifles. It is recommended to double check and ensure proper headspace before firing your rifle. Package Contents: Proof Research PR15 6mm ARC Carbon Fiber Threaded Barrel What firearm models does the manufacturer say Proof Research PR15 6mm ARC Carbon Fiber Threaded Barrel is compatible with? The manufacturer says that Proof Research PR15 6mm ARC Carbon Fiber Threaded Barrel is compatible with AR-15Proof Research 128657: PR15 Carbon Fiber Barrel 6mm ARC 16 in Rifle Length 5/8x24 Thread 1-7.5 Twist 4 Groove Carbon Fiber