DRAGON GAUGE 52mm Air Fuel Ratio Gauge With Narrowband O2 Oxygen Sensor Car Gauge Digital Display Fit for 12V Car 0258006028 1.When powered on digital gauge will read the voltage for 1 minute and switch to Air Fuel Ratio.It will only switch back to voltage if there is a decrease or increase. 2.Air-fuel ratio gauge is suitable for 12V gasoline vehicles 3.The oxygen sensor is suitable for Geely Emgrand Citroen Fiat PEUGEOT Oxygen Sensor Specification: Working Voltage: DC12V Signal Line Voltage: 0-1V Spiral: M18*1.5 Use Wrench: 22mm Output Voltage: Maximum value 900mv/ minimum value 50mv. Response time: (600mV-300mV) 100ms. Response time: (300mV -600mV) 100ms. Starting time: 10s Heating resistance: 8.5~9.5 Internal resistance: 200~300 Connection : The green wire of the gauge 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. About the air fuel gauge, please see the installation instructions. Package included: 1* Air Fuel AFR Gauge 1* Narrowband Oxygen Sensor 1* English Manual(only instrument installation manual, no sensor installation manual) Note: 1.Highly Recommended professional installation,do not teach you how to connect the O2 Oxygen sensor. 2.This kit is not a universal kit, please confirm whether this oxygen sensor is suitable for your car before buying, thank you!