KAK Universal Plan B muzzle devices feature a taper followed by threads resulting in repeatable lockup and a proper seal between the muzzle device and suppressor adapter. Plan B muzzle devices are compatible with Plan B suppressor mounts. FeaturesBore- UniversalMilled flats for easy installation 13/16"Fully Precision Machined in House at KAK IndustryMuzzle devices are engraved with respective thread pitch for easy identification