When I first purchased my boat
there was a tube with some holes in it hanging underneath the radar
unit on the stern arch. I didn't know what it was and never paid any attention to it. Yesterday, it fell to the deck
as the zip-tie that held it in place broke. The tube is PVC, about 2" diameter and 6" long. Both ends are capped and there are five holes drilled in the bottom. There is nothing inside now.