How bright are the led?
Depends on what you compair it with.
It is way brighter than anything usualy used as a tank marker.
I got mine to hang on the anchor line off wrecks to make finding it easier in poor viz, for that it did a good job, but I now use the 3 C cell Tektite strobe as you can see it about twice as far away, but it is also much bigger.
It is bright though, almost as bright as the anchor/running light on the back of my boat.
Mitch - Technical Diver
South Florida Atlantic Side
Works well, long battery life and bright enough for purpose
Don't know the actual specs in candle power but the brightest I've ever used as a kayak 360 degree light