The new NTK Air-Fuel Ratio Monitor Kit (GEN 2) from NGK Spark Plugs has an expanded selectable range of 9:1-16:1 (default) or 9:1-20:1 AFR, a selectable analog output, and a more compact design. Provides a fast response with superb accuracy within 0.1 AFR. The sampling rate display speed is adjustable to your needs. Each AFX kit come complete with control module, wideband sensor, wiring harness, exhaust boss and plug, and a comprehensive tuning manual.