The Faxon Direct Thread Hub is CNC-machined to provide a direct-thread interface between threaded barrels and HUB-pattern suppressors such as Faxon HARMONIX and CORESYNC. This direct-thread hub gives shooters a clean, repeatable HUB interface without the need for additional adapters. FeaturesExternal HUB Thread: 1.375-24 UNS (HUB standard)CNC machined, deburred, and inspectedWorks with most HUB-mount suppressors