Programable Shift Lights: The new Sparco Programmable Shift Lights show you the best time to shift. Our State -of-the-Art Shift Lights are very easy to program due to our integrated self-learning system. All Sparco Shift Lights incorporate a Rev Limiter function, the Sparco SL-C3 Shilt Lights allow the triggering of an output at a pre-set RPM to activate a Fuel Cut, Ingnition Cut or Nitrous or Water Injection. The SL-C3 is designed to be used with 2, 3, 4, 5, and 6 cylinder 4-stroke engines and all Sparco Shift Lights suitable for Trucks, Automobiles and Motorcycles.