question on my air filter

[kikkegek]

hi guys,

I want to start using my original air filter again, but dont understand the function of some parts, please help.

Its from my 350 (original) engine from '86.

1. what is the little green thingy near the red arrow?

2. the metal filter in the center is not removeable as far as I can judge? will it need to be replaced in time?

3. why is this metal filter in there, when there is already a normal filter in there?



this is the EGR-AIR schematic that is printed on it.