The SM-AFR/DM-5 is a true plug and play digital wide band air/fuel ratio monitor. Manufactured by PLX for CB Performance. The DM-5 is a standard size 2-1/16" LED digital gauge. Measuring only 3/4" thick, it can be mounted virtually anywhere. The DM-5 fits into the standard 2-1/16" gauge panel and mounts for seamless integration into your vehicle. The SM-AFR/DM-5 utilizes the latest digital PID and DSP technologies to maximize o2 sensor reaction time and accuracy without compromising overshoot, and slow settling response time. This technology is coupled with advanced self sensor calibration circuitry and sensor soft start to both prolong the life of your oxygen sensor as well as eliminating any user intervention for manual sensor calibration. PLX widebands may be used and installed in your vehicle permanently. Air/Fuel measurement range is 10-20 AFR. 

Below is a picture of what comes with the kit.