THUNDERTAIL REAR WING. For trucks. Mounts to bed rails or flat fiberglass tonneau cover to dress up truck's exterior. Includes built-in 31" super-wide LED brake light. The hottest new look for your sport truck! 9-1/2 in. tall plastic wing material that will complement your vehicle's exterior color or design. Drilling is required for installation. Mounting hardware and easy-to-follow instructions included. Test wing prior to painting and installation for size, fit and possible obstructions (locks, latches, locking pins, etc.)To ensure the proper wing size, measure the width across the flattest area of the fiberglass coverSKU numbers ending in E are freight shipped from warehouse by truck/air freight. A: Outside edges of pedestals. B: Inside edges of pedestals. C: Bolt to bolt. D: Pedestal length.