The same happen to me, arrived did not work. Pissed, sent Huck n Roll an email at 2am my time and woke up to an answer at 7am. Sorry we will send you another keep the one you have. Awesome customer service! Did not bother me with, send it back or just pay shipping, none of that junk. 2 days later new light! As you can see on my photo Lejeune, I ordered another light and now have two working lights, and one dead one (hahaha). The lights are bright enough to use during the day and scares away the darkness!
I slapped these on my 1964 French Champ Du Monde Lejeune Road bike. These lights are so bright you can use them as Day time running lights! I ride in the river beds and there are no lights there. So when the sun goes down you better have some lights. This is the way to go! Going through fwy under paths, tunnels and more, one at the floor and one straight ahead. Not only is it safer by lighting up the whole river bed, but it allows you to push for faster speed when you can see where you are going!