GlowShift’s Blue Digital Series Narrowband Air/Fuel Ratio Gauge monitors your engine’s air to fuel mixture, ensuring it is at optimal levels that result in reduced emissions and better fuel economy. This 2 1/16th Inch (52mm) Blue Digital Air/Fuel Gauge monitors your vehicle’s air/fuel mixture from 10.0 to 20.0 AFR to help you determine if you are running a lean, optimal or rich mixture, but if you are looking to really tune your vehicle we recommend purchasing one of GlowShift’s Wideband Air/Fuel Ratio Gauges. GlowShift’s Narrowband Air/Fuel Gauge includes an easy to read blue LED digital readout, a self-calibration mode, an ultra-thin design, as well as a low profile tinted lens. The included blue digital LED readout allows for all gauge readings to be easily monitored regardless of the angle or lighting conditions, and for easier night driving this air to fuel gauge offers a dimming function that will allow the LED display to dim 30% when your headlights are switched on. This narrowband air to fuel ratio gauge is easily installed to your vehicle’s 0 to 1.1 volt output narrowband o2 sensor with the included color coded wire harness. GlowShift stands behind all of its products by including free lifetime technical support and a one year limited warranty with every gauge purchase.