Proven MYTHIt also improve miles per galon.
Proven MYTH
Like I said, proven MYTH taking a poll from owners dont mean jackNot exactly....
https://www.torquenews.com/4140/does-bed-cover-really-increase-your-toyota-tundras-mpgs
Fire up your Google machine and see what you get. More “yes” than “no” but.....not much at all.