Its a digital sift light system that has a launch feature where you can set your desired launch rpm level. When your holding the clutch (if its manual trans) or the brake (if its auto) the shift light will turn the desired color. once you've reached said rpm's if you are over revving for launch it starts flashing red to let you know to lower the rpm's. also its got a three STAGE SHIFT LIGHT ONE COLOR TO WARN SHIFT POINT IS COMING ANOTHER COLOR TO INDECATE SHIFT TIME AND THE LAST COLOR (RED) LETS YOU KNOW WHEN YOUR DANGEROUSLY CLOSE TO OVER-REVVING...