I see a lot of reviews saying these glasses do not pass the included blue light test. I thought so too, but I was wrong. You are supposed to hold the included blue light LED (yes, there is an included blue LED light with a battery) up to one side of the glass and the blue light card on the other side. The card will stay (mostly) white when the glasses are between the card and the blue LED. The card will turn dark blue if it is exposed to the blue LED light without the glasses to filter it. I'm pleased with these glasses but I will say there are probably stronger filtering glasses out there. That said, they seem to be as strong as some much more expensive blue light glasses I tested in the same manner (Spy+). So, I am happy overall and it is an excellent value!