If you have a Carry-On utility trailer, and you need to replace the marker light, and you want to use the OEM light, then this is what you need. It's made by Carry-On and is a direct replacement. I'm giving it four stars because it is exactly what it says it is. I subtracted a star because at this price, the light housing should last forever, but it doesn't. They corrode inside after a few years. I thought since there's really nothing more to say about this light, I'd talk a bit about the replacement process. Let's start with the inline splice connector, which is the blue thing in the picture. If you have a couple of inches of slack in the wires (which you may or may not depending on who wired the trailer), throw that blue thing away. Those connectors work by piercing the insulation on the source wire, which inevitably causes the wire to corrode by exposing it to the air, moisture, and contaminants like salt. Instead, assuming you have a bit of slack, cut the brown wire where the splice connector used to be and strip off a quarter inch of insulation. If it's green or black instead of shiny metal, it's corroded. Cut it back another quarter inch and strip it again so a quarter inch of conductor is showing. It should be clean there. Next, use an inline heat shrink connector. For 18-gauge wire, which is probably what you have, it will be pink. Cram some corrosion-inhibiting electrical grease in each side of the connector. Then stick one brown wire into one end, and both the other brown wire and the black wire to the light, twisted together, in the other end. There will be enough room for both because the pink connector can be used for wire up to 16 gauge, so there will be a bit of extra room. If you have larger wire, of course, use a larger inline heat shrink connector. Crimp the connections and heat shrink the connector to keep moisture out. Between the corrosion-inhibiting grease your crammed in there and the heat shrunk connector, you shouldn't have any corrosion problems at that splice anymore. Also apply corrosion-inhibiting electrical grease to the mounting screws, especially the back of the head of the screw through which the light grounds. The mounting flange will have a metal ring around that screw hole. That's a common electrical failure point on these lights due to corrosion of that metal ring. The corrosion-inhibiting grease will help prevent that. That's pretty much what it's made for. Next, check the light to make sure it works. Note that because the light grounds through the mounting screw, it must be mounted to work. If it's dangling on the side of the trailer, it won't work. If the light works, carefully tuck away the wires to make it pretty, and you're done.