Storage Key

From the Super Mario Wiki

A Storage Key is a special type of key found in the game Paper Mario: The Thousand-Year Door. Two Storage Keys appeared in the game; both were located in Glitzville. The first one is found in the phone booth after Mario gets an e-mail from "X". That key opens the door to the Storage Room. The second key is found behind one of the posters on the top level of the Glitz Pit after Mario gets another e-mail from "X". That key opens the door on the second floor of the Storage Room.

Keys
Black Key | Blue Key | Card Key | Castle Bleck Key | Elevator Key | Fortress Key | House Key | Key | Luigi Key | Mario Key | Odd Key | Palace Key | Pedestal Key | Random House Key | Red Key | Ruins Key | Shop Key | Skeleton Key | Station Key | Steeple Key | Storage Key | Storeroom Key | Warehouse Key | Wario Key | Yakkey