Jr. Mask is a special item found only in the game Mario Superstar Baseball. It is a Bullet Bill with a bandanna on it, which is modeled after Bowser Jr.'s bandanna. It can only be found in the Challenge Mode of Mario Superstar Baseball. It has to be bought at the shop near Peach's Castle. When bought, it will allow Bowser Jr. to use the Killer Jr. Ball, the name of his Power Shot. However, this item cannot be obtained in Exhibition Mode, as Bowser Jr. can use his Power Shot as much as he wants.
Names in other languages
Musuko no masuku