The Flap Trailing Edge Bulb is a 79.5" aluminum triangle bulb that is used on the trailing edge of the Cessna flaps. The bulb reinforces the trailing edge and is shaped so that it will not stress the skins around the rivets. This reduces the chance of stress cracking and gives a cleaner airfoil. The original flaps on older airplanes did not have a trailing edge reinforcer. The newer airplanes had a flat reinforcer that still stressed and distorted the flap skins. The installation is STC and FAA-PMA approved.