They are used in high-security to ward off the dragons guarding them. The dragons associate the sound of the Clankers with pain and so flee the vault that they are guarding when they hear the sound. The creatures are "trained" to expect torment whenever they hear the sounds produced by these devices, causing them to retreat from the source. They are used by the goblin employees at Gringotts in order to access certain vaults.
In 1998, Harry Potter, Ron Weasley, Hermione Granger, Griphook, and Bogrod (who was Imperiused at the time) used the Clankers to ward off the dragon guarding the Lestrange Vault, in order to get to the Horcrux inside.
Behind the scenes
- In LEGO Harry Potter: Years 5-7, a bull is used to scare away the dragon instead of clankers.
- In Harry Potter and the Deathly Hallows: Part 2, Hermione Granger considered this method as "barbaric".
- Harry Potter and the Deathly Hallows (First appearance)
- Harry Potter and the Deathly Hallows: Part 2
- Harry Potter and the Deathly Hallows: Part 2 (video game)