I have 2 stainless steel fender holders that I don't need. They will fit fenders 11" in diameter or smaller. They are in good condition- used only in freshwater environment. They have a unique mounting system where they can be attached without any additional hardware whatsoever to stanchons and rails. NOTE that they basically fit boats with 1" rails or 7/8" rails and not boats with 3" wide teak handrails so only a good fit for boats with stainless or aluminum handrails.
$100 for the pair plus whatever shipping costs. They are very night but bulky.