Rotor Mallory Flat Cap | Sierra 18-5411 Mallory Flat Cap Rotor | Sierra 18-5411 Rotor for V8 marine engines with crab style Mallory flat cap distributors. Used with 18-5375 distributor cap Replaces Chris Craft 16.69-00042 Replaces Crusader 12531 Replaces OMC 982342 Replaces Volvo Penta 841243