Inner air filter

I was changing the air filter on my 09 Tacoma, and noticed the inner air filter. Does this ever need replacing, and what is it's purpose?

 

It's an emissions thing. Absorbs the last of the vapors from the pcv when you shut off the engine. Only reason to ever remove it was if it got absolutely caked in something, otherwise it's not a restriction and is fine to stay in.

https://www.tacomaworld.com/threads/behind-the-charcoal-filter-4-0.258829/

https://www.tacomaworld.com/threads/charcoal-filter-removal.114126/

https://www.tacomaworld.com/threads/secondary-charcoal-air-filter-removal-poll.121934/

 

Thanks! Thought it might get plugged with fine dust. On an 09.