Also know as a AFR (air fuel ratio) gauge. You can get narrow or wide band. Quote from online:
“A narrowband AFR gauge uses your cars stock O2 sensor for data. ... A wideband O2 gaugeuses a much larger voltage range to determine the AFR. A typical wideband will use 0-5V. This allows for much more precision”
See link for examples, can also get other brands such as AEM, there’s always been a long debate on the best brand of gauge.
https://www.innovatemotorsports.com/