Originally Posted By DaveRS23
https://www.amazon.com/Stainless-External-Marine-Bolt-Supply/dp/B071J75LLQ?ref_=fsclp_pl_dp_

I like to use toothed washers like this between the unit and it's mounting surface along with a bit of grease to avoid corrosion They are available at most any hardware store in most any size.


I use the same thing but I also cover it, when done, with women's clear polish they put on nails. Odd but it works