This top-quality barrel extension set is fully licensed with official trademarks from B&T (Brugge & Thomet AG). It is fully made of metal with a superb finish. The barrel extension tube is designed so that all shots will reliably exit the tube without any obstructions. The included metal flash hider will attach to any 14mm counter clockwise threaded barrel. The extension tube is easily attached to the flash hider using a quick detach locking mechanism. The outer portion of the barrel extension rotates and stays in place with the aid of a ratcheting mechanism. This allows the user to line it up perfectly for a streamlined and authentic look.Includes barrel extension and flash hider.For cosmetic use only, does NOT provide any measurable sound reduction