Brook's ship

The vessel Brook uses to sail around the Florian Triangle. Due to Brook being a pirate it's his pirate ship, although Luffy's crew refers to it more as a ghost ship because of its haunted appearance. The vessel is around 50 years old. It is a large vessel at least ten times the Thousand Sunny's size. While the ship was badly damaged and worn due to time, it was repaired by Franky and was given to and is used by the Rolling Pirates and the rest of the Thriller Bark Victim's Association as Brook decided to finally join the Straw Hat crew aboard their own ship.

Anime and Manga Differences
While the Jolly Roger on the ship's sails is the Rumbar Pirates' Jolly Roger, in the anime however, the ship is shown with a completely different Jolly Roger when it originally appeared and in the episodes following after it.

This error originates from how the design of the Jolly Roger was slowly revealed in the manga. In the scenes in the manga before Brook revealed himself as a Rumbar Pirate, the Jolly Roger was originally obscured by fog. This was done in order to not reveal prematurely Brook's true identity. Because the episodes where his ship has a different Jolly Roger were made before his revelation, the animators used a different Jolly Roger based on what could be made out from the manga at the time.

Though this error is prevalent in most of the episodes before Brook's revelation, a later episode in the anime, that was made after Brook's revelation in the manga, corrects the error by showing a Jolly Roger like the one in manga though albeit obscured by fog.