From Bulbapedia, the community-driven Pokémon encyclopedia.
Pokémon Diamond and Pearl vehicles is a series of toys manufactured by Jakks Pacific. Toys in the series resemble vehicles used in the Pokémon anime. Currently, there are two toys in the set, both of which are based on vehicles used by Team Rocket.
The Meowth Balloon, with Meowth figure (sold separately)
The first toy in the series is Team Rocket's Meowth Balloon.
The Meowth Balloon is designed to be used with Jakks Pacific's Pokémon figurines, however, none are included with the set.
The second toy in the series is Team Rocket's Magikarp submarine, although it is simply referred to (and misspelled) as "Magicarp" on the packaging.
The submarine is on wheels and can be rolled around on a floor or other flat surface. In the back is a propeller that spins as the wheels roll. The submarine has two "entrances": on the left side, there is a doorway to a large interior space underneath Magikarp's fin, and on the top Magikarp's top fin can be moved to reveal a separate, smaller interior space.
Other features of the submarine include fireble torpedoes (including a net) and a periscope.
Like the Meowth Balloon, the Magikarp sub is designed to be used with Jakks Pacific's Pokémon figurines, however, none are included with the set.