Anchor Arms are inflatable muscles SpongeBob uses in the episode MuscleBob BuffPants. He bought them because he was tired of Sandy's exercise program. He saw a shark on TV with Anchor Arms advertising the product. It showed the shark before he got Anchor Arms as skinny and weak. The settings are: Strong, veiny and hairy (for the ladies). Donald the Shark (before picture) is in the episode SpongeGuard on Duty with his family.
Battle for Bikini Bottom
A variant of the anchor arms is used to repair Robo-SpongeBob, after the real SpongeBob temporarily destroys him.