Compatible with all FAST Air/Fuel Meters, the FAST Air/Fuel Meter RPM Module monitors and records engine rpm data that can be overlaid with air/fuel ratio readings. It can be calibrated with the touch of a button and the module plugs in-line with your existing O2 sensor harness. The FAST Air/Fuel Meter RPM Module comes with everything you need, including the installation CD, communications cable, USB cable adapter, power source, rpm module, clip-on inductive pick-up and full instructions to get you up and running in no time.