Little is known about the exterior of the restaurant, but it is shown to have a clam sign similar looking to the Krusty Krab. The letters on the Krabby Krust's sign are painted light red, whereas the letters on the Krusty Krab's sign are painted dark red.
Role in episode
Lost while taking a shortcut to work, SpongeBob sees a sign for a restaurant which he thinks is the Krusty Krab, only for it to turn out to be the Krabby Krust. SpongeBob asks Sal if that's the name of a restaurant, but it turns out to just be a typo.