 As they come up off of turn number four, Jason just mentioned Brad Keselowski liking the clean air. For a new NASCAR fan, Todd Gordon, why is what we call clean air? First of all, what is clean air? And secondly, why is it so valuable? I love the analogy you used yesterday. It's like being behind a boat. So the water behind a boat, it gets turbulent. You see it all messed up. That's what happens with the air behind these race cars. So the guy that's out front, the air is still. It works. It makes maximum downforce, especially that undercar area.