FSNDS is an edgetoedge NDS skin with an option for reactive LEDs. The LEDs are based on the screens of whatever you are playing. That's why there are two LED options, 1 which is based off the top screen, and 2 which is based off the bottom screen. There is a centered option where the buttons are in the center for more comfortable playing, and there is a normal option where the buttons are on the bottom of the screen.