Hi,
Very observant of you...
That's a cable tie being used to "secure" the round clevis ring. To make a long story short: In a pitch-pole during one leg of the 150 mile Down-the-Bay regatta, my co-skipper, Dr. Ron Jones, had some part of his clothing rip that little ring right off as he shot past it - almost lost the foil. Though I taped all the rings around the boat, I had forgotten those two. The cable tie also holds the ring up to prevent that little white galvanic corrosion where the stainless ring just touches the aluminum - a nice solution for us anal-retentive / obsessive-compulsive types...

Steve