On my 2007 G35 sedan, these are in front of the rear tires. One is hanging on for dear life, so, figured to pick up a replacement (do these just clip into place, or, is there more to them removing/installing them?)

Appreciate any feedback!

 

I have the same on my 07 and I don't see their purpose. Someone at Nissan, somewhere in some basement thought that these flaps do something but I don't see what..

 

They are held in place with the plastic push pins found all over the inner fenders and splash shields in all Nissans. As for their function, they are part of the aerodynamic kit to reduce air drag by the tires by diverting the air flow downward.