The Endura Flap rod is the pivot rod that the flap swings on. It is pretty rare to bend a flap rod, but we have seen it happen when a dog plays tug of war with the flap.
The flap rod is held in with retainer washers, and these washers are included with a flap rod order. Replacing the flap rod requires access to the washers. For a door, wall or kennel Endura dog door, you will need to pull the frames off of the wall. For Thermo Sash 3e window cat doors or Thermo Panel 3e and Quick Panel sliding glass doggy doors, you will have to disassemble the frame, sliding the pet door frame out of the larger pet door panel frame. Click here to see a video explaining how to adjust the rise on a Thermo Panel - it shows removal of the flap frame from the larger panel frame.
Most doggy door flaps are soft vinyl and are screwed into the frame, and just flex to open. Endura Flaps are soft, but are hung from a hinge. The hinge saves a lot of the wear and tear that occurs on vinyl flapped pet doors since they don't have to bend back and forth to open.