 The air in your home balanced from downstairs to upstairs. And that balance alone keeps you way cooler. And you don't have to run your AC as much. In fact, you'll save money. That's number two. So you have attic ventilation. Then you have what I call destratification. And that would be I wouldn't use anything but the quiet, cool whole house fan. And you can look it up online and see who the dealers are out there.