This is a sweet item! Check out the documentation to understand what all this unit can do! Does AFR/Lambda/Universal display, data storage, etc. Fully user configurable through two easy-touch buttons. Available in red (brighter) or blue (not as bright but looks cool!). Blue is a little more because of the parts cost.
Here is the instruction guide for the O-Meter so you can read about all the features:
Here are pictures of the wiring, as well as a picture of the 'BLUE' O-meter:
Here is a video of the O-Meter in action: