Volvo Penta DPI-A Magnesium cavitation plate anode.
If your anode is worn away by 33% or more, it is advisable to change it, as more of its surface area has been worn away and the remaining anode will wear away much quicker.
Please note this is a Magnesium anode for fresh water.
Volvo Penta Part No: 23520859
For: DPI, DPI-A