We spent a lot of time making sure that Remee's lights were configured in such a way that it would work well for all face shapes and head sizes. Six lights creates a much larger effective signal area so that even if the mask shifts during sleep you'll still most likely have at least a few lights over your eyes.  Even cooler, by having six lights we make it possible to create much more unique signals that can strobe, sweep and blink in ways that are not only recognizable, but that stimulate your visual field in a more tangible way.  In addition,  red light penetrates skin much more readily than other wavelengths.  Remember when you were a kid and you put a flashlight in your mouth to make your cheeks glow red? That happens because red light is able to pass through your skin, and in the case of Remee, your eyelids, much more easily.  On a side note, red LEDs also use much less power than other colors so we were able to keep you from strapping a 9v battery to your head.