Looking in the boot, the side that face the front where the latch is, are openings that are stuffed with dark grey mushy foam, like used as packing cushion. Is this some kind of filter?

 

This is the unknown air vent.. what it does, we're not quite sure...

Rocketboy_X

 

According to the dealer, its to project the sound of the exhaust. It does seem to help. Notice on the top of the rear deck lid there are similar holes that serve the same purpose. My Boot Box blocks the vents on the bottom though, so I can't hear the exhaust quite as well... but my Pilo intake is so loud it doesn't matter,