Volvo Penta 280, 290 DP Propeller Nut for A, B and J series propellers.
This is item 10 shown in the diagram. It has 3 raised prongs.
This inner nut fits some DP-C, DP-D, DP-E, DP-G and some 280 DP and 290 DP drives.
The tool to remove it is part number 873058.
The other inner nut option has multiple prongs and is part number 852196 and has 9 raised prongs. The tool for this type is part number 885127. Generally, this nut is used on DP-A, DP-B, some 280 DP and 290 DP sterndrives.
If you need help sizing a correct propeller size for your boat, please contact us first.