A couple of years ago there was a thread concerning our H37C running lights(Related Link). The consensus was that these were series 25 from Aqua Signal. Not! Lying here on the floor is a box from Sailnet with two new series 25 lights, bow and stern. They are too small. My boat has lights with an NSK marking. They are larger and have a stainless body. But the lenses are fogged and cracked. Since I plan to do a fair amount of motoring in the ICW next year I want to have highly visible lighting. And guess what? Right, the series 40 lights are plastic and cost three times a series 25. You can buy the series 40 lenses from Aqua Signal but there is no way to know if they would fit the NSK light housing. That is why I ordered the entire series 25 light. So I guess it will be black plastic at $55. each. 