Faxon Firearms 1/2x28 Barrel Adapter Titanium Titanium. 28 barrels. The Faxon Direct Thread Hub ?28 is CNC-machined from Grade-5 Titanium (Ti-6Al-4V) to provide a lightweight corrosion-resistant direct-thread interface between ?28-threaded barrels and HUB-pattern suppressors such as Faxon HARMONIX and CORESYNC. Specifications for Faxon Firearms 1/2x28 Barrel Adapter: Manufacturer: Faxon Firearms Finish: Titanium Fabric/Material: Stainless Steel Features of Faxon Firearms 1/2x28 Barrel Adapter Material: Grade-5 Titanium (Ti-6Al-4V) Internal Barrel Thread: ?28 UNEF (direct-thread to barrel) External HUB Thread: 1.375-24 UNS (HUB standard) Finish: Natural titanium CNC machined deburred and inspected Compatibility: Works with most HUB-mount suppressors; tested for fit with Faxon HARMONIX & CORESYNC when the correct hub configuration is used Package Contents: Faxon Firearms 1/2x28 Barrel Adapter Faxon Firearms FF-MD-SIL-HUB-5-28-02: 1/2x28 Barrel Adapter Titanium Titanium