I have a used Monitor windvane wheel adapter. This was purchased with the later 316L model vane gear, so presumably the same material. I don't know much about these, but appears to be in excellent condition with the exception of a little surface staining from where the adapter mounted to the spokes of the wheel. These go for $575 new from Scanmar, but I'm asking $250 or best offer shipped to continental U.S. Willing to ship to HI or AK, or internationally, but additional shipping may apply .