This actually worked. The information on the Amazon page says it will catch things like leaves coming into the air circulation intake. Well, it's a Tesla, how bad could the engineers have made the intake? Badly, it turns out. There is a plastic cover in the frunk which removes to reveal the 12v battery on the right and, coincidentally, the air intake on the left. It really is just a couple of large squareish openings. And indeed, there was a leaf inside the thing. I guess Tesla expected the cover, which removes by simply pulling it off, no tools at all, to prevent debris from getting into the intake. That design is not sufficient after all.
I installed this grille cover in seconds. It fits neatly and securely right into the intake, fitting and looking like OEM. It has some 3M adhesive around the edges to be sure it stays secure and won't rattle. So to install, you pull the cover, remove the tape from the edges of the grille, insert it into the opening, and then replace the cover by popping it right back on. It's great and takes less than a minute start to finish.
Air will still easily get into the system, but anything larger than the diameter of a small straw will not make it.
No more leaves for me.