52mm Air/Fuel Ratio Gauge Pointer Display Red Backlight with Narrowband O2 Oxygen Sensor Gauge Cup Fit For Car 12V Specification: 1.Fitment: Fit most of 12Volt gasoline vehicle, Fit 2"or 52mm Diameter Gauge Pods holder 2.7 Colors : Smoked Tint lens when off,Color LED Display when on 3.The gauge will both show the digital and analog LED. 4.Electrics voltage display & warning function. Connection : The white line is at heater ab Black line signal line C, gray line signal ground D The green wire of the instrument is connected with the black wire of the sensor. The gray line is connected to the negative pole of the battery. One white wire connect with the car shell or battery negative pole. Another white wire connect to the ACC line of ignition switch The white line is the heater and does not distinguish between positive and negative electrodes About the air fuel gauge, please see the installation instructions. Note: There are multiple collocations for this product, please purchase according to your own need requirements. Package Included: 1 X Gauge Package Included: 1 X Guage 1 X Sensor Package Included: 1 X Sensor Package Included: 1 X Guage Cup