Air box stock prefilter?

Here's another air box question for you guys!
I have an 06 trd prerunner with the k&n air filter insert. Noticed that there's a stock prefilter in the air box that looks like white cotton with metal lattice on it. The k&n insert sits right next to it.
Is it necessary or should I take it out?
If so does it come out easily so I can clean it?

Thanks
Cliff

 

That's a good question I have the k&n filter but wondering how to clean the white filter

 

It's not a "prefilter" and if it needs cleaning, then that tells you how good the K&N is

 

So charcoal, not a filter... I just used a vacuum myself i saw a post that you gotta take out some rivets in order to take it out so if it ain't broken dont fix it i guess... What filter do you have on it Rich? Any suggestions ?

 

OEM and nothing but.

$16 online from Camelback or Titus-Will.