The way I see it, LED (cluster types) bulbs put into incandescent fixtures doesn't change anything but battery draw...and using less juice on trailer lights isn't a concern to 99% of trailer boaters. Those fixture aren't sealed tight like LED fixtures. Submergible incandescent fixtures have a small vent on the bottom to let moisture out. It breaths enough to let condensation happen even if water never "leaks" in from launching. It's not that difficult to make standard submergible fixtures work for yrs and yrs of dunkings without problems. Take the lens off and remove the brass bulb holder. It comes out in pieces and most are a press in friction fit. Liberally coat ALL metal surfaces (back and front) with dielectric grease. Liberally coat inside the bulb socket and bulb base up to the glass but not over the glass. Glob it on the bare wire connections. Leave no uncoated metal inside the fixture. Assemble everything and make sure the lens gasket is good. Caulk the fixture where the wires enter (LED users should caulk their wires for better life too). Apply grease to the harness connectors. This pretty much eliminates trailer light issues on submergible's and works as well on nav lights. How long? I have one trailer going on 12 yrs of saltwater launching and not even a bulb change yet. Avg life on these units in my Florida neighborhood is 3-5 yrs without coating with grease...and I see several a week. My other trailers (3) share one set of clip ons that don't get wet. Bill **************Get trade secrets for amazing burgers. Watch "Cooking with Tyler Florence" on AOL Food. (http://food.aol.com/tyler-florence?video=4?&NCID=aolfod00030000000002)