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Join Date: Sep 2005
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Looks to me like a piece cut to fit the deck partners... where the mast goes through the deck, installed from inside with the 'flange' side down. It would take the place of wedges often used here to locate the mast within the partners.
If the narrower parts match the deck cutout that should be it.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)