Thanks!
Thats an o2 sensor for a Dynojet WideBand Commander. Basically an A/F guage, tells how rich or lean the carbs are. Doesn't control anything, just gives you the A/F ratio.
The brain also has inputs to monitor RPM (The only extra thing I'm using), it can also monitor throttle position, manifold boost or vaccum, oil pressure etc, if you want to hook it up. The A/F is the only thing thas\ displays, everything else goes into a datalogger you turn on with a switch and then you can view the files with a laptop. I stole it off my wifes hot rod that was supercharged before we sold it so that's how it ended up on the bike.