PROOF Research shouldered pre-fit carbon fiber barrels for Zermatt Arms RimX actions make it easy to upgrade your rifle or change calibers. The pre-fit Zermatt Arms shouldered barrels are easy to install. Simply thread it on, torque it down, double check headspace and head for the range. These carbon fiber-wrapped barrels provide a high end alternative to traditional barrels while still maintaining extreme accuracy, performance and durability. Match-grade accuracy Improved heat dissipation for cooler and longer lasting barrels No point-of-impact shift during high-volume fire Reduced harmonic barrel vibration Mfg: Proof Research