Rearden FHD Features The Rearden FHD Flash Hider is machined from 17-4 PH steel and finished with a Black Nitride coating that reaches 67 HRC surface hardness giving the device the durability to withstand repeated suppressor mounting and dismounting. It is designed to be compatible with Plan B type mounts including Atlas and Atlas XL systems and includes an Atlas XL adapter for added flexibility across mounting standards. The nitride finish helps create a tighter seal between the flash hider and a suppressor though Rearden stresses that the device must still be properly torqued and Rocksetted to the barrel to achieve reliable alignment. Updated wrench flats on the rear of the device make installation and removal easier compared to earlier versions. Correct installation calls for torquing the muzzle device to approximately 30 ft lbs after ensuring all mating surfaces are clean with the suppressor itself torqued to 10 ft lbs once mounted. An alignment rod should be used throughout the process to confirm the entire system lines up correctly before live fire. Shims are not included so barrels without a factory thread relief may require a shim for proper timing. Builders assembling a dedicated suppressor host on an AR-15 platform will find the FHD Flash Hider a precision option engineered specifically for Plan B style mounting systems. Rearden FHD Specifications Manufacturer: Rearden Model: FHD Compatible Hosts: AR-15 Color: Black Material: Steel Finish: Black Nitride Thread Pattern: 13.5x1 LH Item Length: 1.723 Weight: 0.126 lbs Available At: GrabAGun