1990's Pontiac Grand Am Sedan fender and quarter panel
On an automobile, a quarter panel (or rear wing as it is known in British English) is the body panel which goes between the rear door and the trunk and typically wraps around the wheel well; the similar front section Fender (vehicle), between the door and the hood, is sometimes incorrectly referred to as a quarter panel. The quarter panel is typically made of Sheet metal, but is sometimes made of fiberglass or fiber-reinforced plastic; depending on the construction of the specific model.
A quarter panel is typically a welded on component of the uni-body structure. Replacement of a sheet metal quarter panel typically requires it to be cut off the vehicle and a replacement part to be welded (or sometimes bonded) to the vehicle. Due to this high amount of specialized labor, a quarter panel may often be repaired rather than replaced by hammering out the damage, and a body filler applied to finalize the original surface.