What sensor is this ???

[Micksan]

On the top right side of the air box ,just below the cover . There is a sensor screwed in. It has a conector attached to it with three pink wires.
I have installed the the three individual K&N air filters onto the throttle bodies. The air sensor that was in the pipe coming from the airbox to the injectors I have a small K&N on it. So what do I do with this other sensor. My plan is to remove the airbox and install a air horn.
Thanks

 

[snowbandit]

I was told its air pressure and to just leave it.