EASY INSTALLATION: Wideband AFR gauge is made of high quality materials and technology and is easy to install thanks to its standard 52 mm housing. You can easily install it in almost any location. at the same time, it never requires free-air calibration when used with our wideband O2 UEGO AFR gauge.Notice:It can only be used as an AFR Gauge for observation and monitoring, and cannot be connected to a computer terminal for analog output Flexibility and Expandability: The controller box in the kit is highly flexible and expandable. You can adjust and expand the controller box configuration to meet the requirements of different vehicles and applications. The ability to customize the controller box's connections and parameters according to the engine management system's specifications and personal preferences to achieve the best fit and performance optimization WIDE COMPATIBILITY: Our air fuel ratio gauge comes in a standard 52 mm (2-1/16 inch) housing that fits in a variety of instrument pods, providing flexible mounting options.Compatible with vehicle/system voltages up to 16 V.Please turn on the power after completing the connection, and be careful not to operate with electricity when plugging or unplugging the device Applicability: Air Fuel Ratio gauge compatible for 12 volt car. High sensitivity and easy operation. Function: Numbers clearly show, LED backlit for easy reading in the darkness. Versatile design: In addition to measuring and displaying the air/fuel ratio, the Air/Fuel Ratio Gauge also features a broadband measurement and digital display. This means you have access to more comprehensive data and into your engine's combustion state for precise tuning and optimization Color: Black Material: Plastic The appearance of the product slightly from batch to batch, but will not affect the use Package Contents: 1 x Air Fuel Ratio Measurement Kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.