
It is an unterminated name glitch item, hence provides the effects associated with those glitches and allows for glitches such as Yami Shop glitch and LOL glitch.
If a 0x50 sub-tile is early enough in the saved screen data, then this item will act as a Rival's effect glitch item which opens the menu from both in and outside of battle. From outside of battle, if the player exits the menu with B they can enter a glitched state where they can walk through walls that are one tile thick. If the player selects a Pokémon without full HP instead, it will heal up to 80 HP and use up one of the item.
This glitch item can be used as a healing item for up to 80 HP within battle if a 0x50 sub-tile is forced early in the saved screen data with GameShark code 0150A0C3 (or theoretically OAM DMA hijacking).