If you were looking for the article about the single iron butt, then see Iron Butt.
Iron buns are a body part that appear in the episode "Krusty Krushers."
Description[]
Iron buns are a pair of metal buttocks that Patrick develops after a large amount of butt exercising in preparation for the main wrestling competition.
Role in episode[]
Patrick had previously done various butt exercise that made his gluteus maximus strong. It is also shown that he developed them while he was sleeping. As a result, Patrick is able to generate his iron butt within seconds before the two wrestlers can "drill" onto SpongeBob and him on the bed that is in the main stadium.