a radio - frequency radiation suppressor component for use with magnetrons that reduces spurious leakage radiation by absorbing rf radiation , that seats a metal ring connector fixture for making electrical contact to the cathode of the magnetron , and that exhibits improved tolerance of higher operating voltages . an insulated rf suppressor component is comprised of an insulating sleeve member and an outer shell cladding layer made of molded composite iron powder / epoxy resin material that absorbs part of the rf radiation and thus acts as an absorber to reduce magnetron radiation leakage . the insulating sleeve end has a ridged groove indentation to seat a metal clamping ring that contacts the magnetron cathode and provides a terminal connection for the cathode voltage bias and filament heating circuit leads . testing of prototypes indicates significant improvement in permissible operating voltages and comparable rf suppression compared to conventional rf suppressor components currently in use .