Mercury Zinc Trim Cylinder Anode | Martyr CM806189Z Martyr trim cylinder anode protects trim cylinder from corrosion in salt water. Mercruiser trim cylinder anode For Alpha I Gen II 1991 and up Zinc anode for salt water applications Zinc aftermarket replacement for aluminum Mercury anode 806189Q1 For aluminum see p/n CM806189A For magnesium see p/n CM806189M