I'm getting ready to put together my cold air intake. I have a cone filter in a closed box mounted directly on the MAF, and a hose running down as a cold air draw. Here's the question: The hose that runs from the valve cover to the airbox, and has a little sponge thing where it comes out.. What is it? I've tried looking but I don't even know what to search for because I don't have words to explain it.

When I install my new intake, where should I run this hose to? Can I replace it with a breather filter, or just hook up the other end to somewhere on my cold air draw hose?

Any advice would be appreciated. I don't like to start new threads about things that have surely been discussed before, but I don't even have a clue on what to search for.