Offset air cleaner questions.

[In The Ten Ring]

I tried to get you guys pics of this but Photobucket.com is not cooperating.

My unit has a snorkel and inside of there is what appears to be a vacuum-operated valve. Why would it need a valve? Do I need to have a valve there?

My lower of the two halves has a tube sticking out the side that holds a fiberous material on the inside. What might that be for?

My lower also has a plastic clip of some sort on the floor (of the pan). What might that be for?

It was also VERY greasy, all on the inside and even outside. Would that make mine an "oil bath air cleaner?"

If so, may I use it as a standard air cleaner (non oil bath)?