Well, we cranked it up.....it is EXTREMELY BRIGHT!It is actually an indoor lamp replacement for a MR 111 halogen. Of course, it is used indoors with a 12V transformer.It produces no heat, and draws hardly any power. I'm thinking it could be used as a spreader light inside one of those old Perko bullet style chome on brass fixtures.Looking at it, if it were well sealed, I don't think corrosion should be an issue. Mine is going in a standard flounder light, for underwater use. The LED lamp has decorative metal fins, that look like a heat sink....totally unnecessary. I am in process of cutting those off with a dremel, so it will fit inside the glass globe of the flounder light.I'll let you know how it holds up. Good news is, it puts out a ton of light, should give great visibility.Scott