There are conservatively 500,000 Extang Tonnos on the road everyday and based on the average gas savings, we save America 60 million gallons of gas per year or approximately $100,000,000. Studies show the average truck owner drives 18,000 miles per year. At 15 mpg that comes to 1,200 gallons of gas. At a minimum 10% savings you would save around 120 gallons a year (and many reports show it to be more like 12%). You can see why it would not take too many months to have your new tonneau pay for itself.