Rearden MFG R2C Rainbow PVD Flash Hider 1/2-28 Black Rainbow PVD. Always use an alignment rod to ensure that the entire system is set up correctly. Make sure all surfaces are cleaned and the muzzle device has been torqued and Rockset to the barrel. Torque the muzzle device to approximately 30 ft lbs. Make sure the muzzle device is square against the shoulder. When setting the silencer on the muzzle device ensure that the threads and tapers are clean. Torque the suppressor to 10 ft lbs. Ensure alignment. Enjoy. Specifications for Rearden MFG R2C Rainbow PVD Flash Hider: Manufacturer: Rearden MFG Color: Black Rainbow Finish: PVD Features of Rearden MFG R2C Rainbow PVD Muzzle Device Atlas and Atlas XL Compatible Plan B Compatible Atlas Adapter Overrun Approximately 1.600? Atlas XL Adapter Overrun Approximately 0.750? Package Contents: Rearden MFG R2C Rainbow PVD Muzzle Device Shims Rearden MFG 10120: R2C Rainbow PVD Flash Hider 1/2-28 Black Rainbow PVD