Kase 77mm Magnetic Converter Ring for Threaded Filters

The Kase magnetic converter ring allows you to convert conventional screw-in filters to the magnetic type. It's magnetic on one side and has a female threads on the other. Screw your threaded filter onto this ring, and then magnetically mount this ring onto the male-threaded magnetic adapter ring. (The male-threaded ring is the one that screws onto your camera lens and provides a magnetic mounting surface.)