At 1/4 the cost of the failed premium LED boat trailer tail lights they replaced; these are a great value that appear to be vastly superior. I expect thay will last a long time.Housing is not sealed and has has drain holes top and bottom, wires pass thro an open hole. Presumably, all LED and electical element are sealed. Wires appear to be tinned copper. Haven't dunked the boat just yet, but I am pleased with the design. In my experience, un-tinned copper wire corrodes away to nothing after a couple of seasons of use - tinned copper wire, e.g. Ancor, does not. Wiring pigtails with connectors provide extra areas that corrode and fail. Sealed housings tend to lose their integrity after which the water is trapped inside the housing, slowly killing the unit. I Installed using stainless studs/nylock nuts & heat shrink solder sticks, for waterproof wire splices. Supplied metric mounting studs/locknuts are not stainless.