Rearden MFG FHD Rainbow PVD Flash Hider 5/8-24 Tapered Shoulder Black. 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. Use on a Q can voids your warranty be warned. Torque the muzzle device to approximately 15-25 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. The nitride finish does lead to a tighter seal with that said it is extremely important to torque and rockset your muzzle device to the barrel properly. Specifications for Rearden MFG FHD Rainbow PVD Flash Hider: Manufacturer: Rearden MFG Color: Black Finish: PVD Features of Rearden MFG FHD Rainbow PVD Muzzle Device Atlas and Atlas XL Compatible Plan B Compatible Atlas Adapter Overrun Approximately 1.050in Atlas XL Adapter No Overrun Shims Not Included if you would like to specifically time this shims will be required. Note: your barrel may require a shim if the manufacturer did not put a thread relief on it. Package Contents: Rearden MFG FHD Rainbow PVD Muzzle Device Shims Rearden MFG 10128: FHD Rainbow PVD Flash Hider 5/8-24 Tapered Shoulder Black