A multi-panel cover includes end panels that connect first and second lateral panels. The lateral panels seat against the tailgate assembly of a truck body and are maintained in position by magnets incorporated into a lateral panel along the edges and between the side panels to form a pocket to collect debris that may otherwise escape through or around the tailgate of the vehicle. A peripheral sealing material such as an elastic cord or hook and loop seal may be positioned around the tailgate gap to augment sealing.