If your boat has the newer type of drain fitting that is a plastic thumb screw, this is the adapter you need. It comes with the adapter only. Your o-ring will fit on it and our light screws into the female end. Simply just adapts your thread to our thread. Can be used with all of our drain plug lights (except of course our rubber expanding plug)
NOTE: Although described as Yamaha, seadoo etc.. Look at the pictures provided and make certain by comparing yours, yamaha boats have at least 4 different types of drain plugs that we are aware of.