The anode kit number (serial) is 888756k01,
Are we sure this is for fresh water?

"The Mercury Marine Complete Anode Kit 888756K01 is suited for use on 1991 and newer Mercruiser Alpha One Gen II Outdrives (s/n 0D469829 and up). The kit is a full replacement for all factory installed anodes found on the transom and drive unit. Aluminum construction makes them useful in all types of water."