We use our triple axle boat trailer in salt water all the time. Over the years we have seen many so called sealed tail light and marker light assemblies fail miserably due to salt water intrusion. The will be the third pair of sealed LED tail light assemblies we have bolted on to our trailer. Whenever I replace lights on our trailer I soak test them. These survived about 2 days in 2 feet of tap water with no visible water intrusion, so I bolted them on to our trailer yesterday, time will tell if they stand up to salt water use.
(3 of 3 people found this review helpful)