This is the actual light generator-a red, green, blue LED circuit, protected and sealed by a clear-plastic, 3mm-thick overmold. It will be attached to and shoot down the light tube of the same thickness. This RGB architecture (rather than a single-color LED) can generate almost any desired hue, depending solely upon how its harness is wired. In fact, for customers having the factory Ambient Lighting package on their '10-and-up Mustangs, the color on the scuff-plate display will change with the color of the car's lighting setting. Otherwise, you can pick from eight available colors when ordering.