When buying underwater lights for your boat one of the main things you want to know is whether the lights will be bright enough to make it look great.

Therefore the Luminous flux, i.e., how much light do you get from the fixture is the figure you should be looking for in the lights' spec. It’s measured in lumens (lm). 

It can range from less than 1000 lm used on small crafts/tenders and even jet skis to more than 25,000 lm lights on a large superyachts. The more the merrier, however depending on your yacht / boat size you can hit the right spot with the variety of models available.

For example, for a 15m (50ft) yacht a 6000 lumens should give you a decent look, depending on the areas/waters you operate in.

*Tip: Divide the light price by number of lumens to see which light gives you better value per lumen.

Some manufacturersmight get tricky and only mention power in Watts, which doesn’t really tell you how much light you get for your buck, so to have an idea, you may try to convert the stated Watts into Lumens using many online calculators available, for example:  https://toponlinetool.com/watts-to-lumens-calculator/

You’ll need to factor in the Luminous Efficacy in that formula – it varies quite greatly depending on design & manufacturing quality, from 40 to 90+, guess you get the idea...

Please feel free to contact us if you have any question or need recommendation on what lights would suit your boat and we'll try our best to advise.