Magnesium Martyr anode protects bearing carrier from corrosion in fresh water lakes and rivers. Magnesium Bearing Carrier Housing Anode | Martyr CM431708M BRP/OMC bearing carrier anode Magnesium anode for use in fresh water applications 3 in long 2 in. wide 0.9 in. high Magnesium aftermarket replacement for zinc BRP/OMC 0431708