The AEM X-Series Wideband UEGO Air/Fuel Ratio Sensor Controller Gauges have patent pending X-digital technology that makes them the fastest responding wideband air/fuel ratio controller in independent testing against 17 other wideband UEGO controllers.The X Series Wideband UEGO AFR Sensor measure 52mm in diameter and has a slim depth less than one inch with an ultra slim cup of .200 inches increases this gauges application base and potential mounting locations. The gauge has a configurable display via buttons on the face of the gauge these allow you to change the air/fuel ratio values for different fuels, lambda or O2%, change the display to show either 3 or 4 digits, perform a free air calibration as the sensor gets older and change the CAN message if linking multiple controllers or gauges.This kit has a black bezel and black dual faced faceplate for air/fuel and lambda. An auto dimming feature is also included, comes with locking connectors that ensure a positive connection is made between the harnesses and gauge and the new single board design adds to the durability of the gauge.The gauge comes with a 0-5v and RS232 seriel port output for feed back and data logging and an AEMnet output for data logging. AEMnet allows additional X Series wideband controllers to be daisy chained together for recording air/fuel ratios in multiple cylinders.The system supports vehicle/system voltages up to 16V, and can be used on electronic fuel injection or carbureted applications and dynamometers in applications using petrol, methanol, ethanol, diesel, propane or LPG.