Clear Bell
The Clear Bells (Japanese: クリスタルのすず Crystal Bells) are bells installed in the Tin Tower.
In the anime, they were said to announce the coming of Ho-Oh. They were stolen and broken by Team Rocket which precipitated the events of For Ho-Oh the Bells Toll.
The bells appear to have magical properties as the Pokémon were able to sense that they were stolen.
The bells were also built in a way that they cannot be rung by force. How it is made that way is still unknown.
The Clear Bells have been misnamed Crystal Bells in 4Kids dub, because of literal translation of Japanese name.
In the games
In Pokémon Crystal, the Clear Bell is given by a person in the Johto Radio Tower. It allows the player to battle Suicune at the top of Tin Tower. Suicune will not flee and the player will be unable to leave as well.