SpongeBob wears a Mermaid Man suit that looks almost identical to the real Mermaid Man's costume. It is orange and square-shaped to fit SpongeBob. It also has Mermaid Man's head at the top along with his purple "M" belt. As well as this, there are greenish-blue gloves and pink slippers on the suit.
Role in episode
After Mermaid Man and Barnacle Boy are injured and sent to the hospital, SpongeBob and Patrick go to visit them. Mermaid Man and Barnacle Boy receive a call from the police commissioner, telling them that they will be celebrity guest contestants at the Bikini Bottom shuffleboarding competition. They are unable to attend in their condition, but SpongeBob then says both he and Patrick are certified Mermaid Man and Barnacle Boy impersonators. They are given rings that produce rubber Mermaid Man and Barnacle Boy costumes, and are told to immediately return them after the tournament.