From the Super Mario Wiki
An Item Bag as seen from Mario Party 4.
An Item Bag from Mario Party 3.
A Item Bag is an item that is found in Mario Party 3 and Mario Party 4. In Mario Party 4, the sack bag has question marks all over it.
The player can acquire this item by purchasing it from an ordinary Item Shop within the two respective games. It costs thirty Coins. When purchased; the player automatically opens the Item Bag, revealing three random items. It can contain common items or even rare items normally not available for purchase from Item Shops. In addition, the bag can contain a pair of the same items or all three different items.
If the player has one or two items held in the player's inventory, the player can only acquire one or two new items depending how many are already in the inventory. The remaining item or items in the bag remain inside and then the bag is discarded.
Names in other languages
||Sac à Objets
||Sack of Objects