Prop Anode Bolt Size - 2014 R31

[Happy Place]

Noticed that the anode and bolt are missing from the end of my prop shaft.

Assuming 316 stainless, does anyone know the type, size and pitch of that bolt?

 

[S. Todd]

Assuming it is the same as what is on the 2021 R29 (1 1/2 inch shaft) it is a 5/16ths X 18. Threaded portion is 1 inch. Head is 1/4" so entire bolt is 1/1/4" long. Head uses a hex wrench. If you go to BoatZincs.com it is shown as Propeller Nut C/D/E/F Mounting Screw ($1.87).