Pro-Shot cleaning rod features the Proprietary Rod handle design which allows the rod to rotate in the handle, allowing the bore brush to spiral with the rifling and clean the grooves completely. Compatible with 27 Cal firearms and up. *Note- #AD2 Brass Adapter- This accessory is not a thread adaptor. The #AD2 is meant to make a smooth transition for the .27/U diameter rods to accept smaller diameter accessories, such as a bore brush or patch holder.