FAST? engineers have developed a kit that makes it easy for anyone to measure an engine?s air/fuel ratio. This plug and play universal O2 sensor processing kit allows your data acquisition system or dyno software to record and display air/fuel ratios. Since it uses fully automatic sensor calibration, there?s no need for manual ?free-air? calibration that competitive units require. Additionally, each sensor kit is a standalone unit, so using multiple kits for measuring all your engine?s cylinders is easy. Compatible with FAST? Digital Air/Fuel Meters.