This LED bar graph display is basically several individual Light Emitting diodes in a single package. Each of the diodes has its anode and cathode pin connection outside the package. Like Light Emitting Diodes, current flowing through the individual LEDs of the bar graph display must be limited to avoid damage. Consider using these displays in your audio projects or any project requiring a bar graph-like display of a quantity for example, water level in a tank, battery level, sound level etc.