Kaito's Pendant is a box that Kaito has in the first episode of Mermaid Melody Pichi Pichi Pitch. Ever since Lucia gave Kaito her pearl to save his life, he kept her pearl as a memory of them meeting for the first time as children. In Mermaid Melody Pichi Pichi Pitch Pure, when Kaito lost his memories, he gave the pendant that symbolizes his most precious possession (Lucia) to Mikaru Amagi, after she asked him whether was more precious between her and the pendant. Later, close to the end of the season, Mikaru gave Kaito back his pendant, symbolizing acceptance to the fact that Kaito chose Lucia and giving up on him.
The pendant is a rectangular box fixed to a chain. On the top of the pendant, there is a small symbol that is possibly the Panthalassa mark. It used to hold Lucia's pearl for seven years. Now that Kaito returned the pearl to Lucia, it's empty for the rest of the series.