Many Beneteaus came from the factory with gas discharged lightening arrestors, mine did and so did my buddies 375. I thought it was some kind of fuse and was opened and thru research discovered it closes on a strike ,so the boat is not grounded to the keel ,only if its hit .It goes from starboard chain plate to arrestor then to keel , so I ordered a second one off ebay and ran a second one from portside chain plate to keel