You haul anything from hardware and tools to your weekly groceries in the bed of your pickup truck. A tonneau cover will keep all of it under cover, protecting your cargo from not only the elements and bad weather, but also from would-be-thieves. Adding a tonneau cover to your truck bed is the easiest way to make sure nothing disappears from your bed while you're driving or parked. They also provide better aerodynamics, therefore increasing your gas mileage.