The Iron Butt is a device was only mentioned and shown in the episode "I Had an Accident."
It is a large gray machine with many wires, gears, pipes, and other things sticking out of it.
It is a machine that doctors use in Bikini Bottom if a patient's butt is severely injured. Tom once had to use one. SpongeBob fears the Iron Butt greatly.
- The Iron Butt is a parody of a device called the Iron Lung, which is used for breathing problems because of Polio.