|Gringotts vault key|
To open bank vaults
These were gold keys owned by anyone who had a bank account at Gringotts Wizarding Bank, enabling them to unlock and withdraw from their vaults. Lower security vaults, such as the one belonging to the Weasley family, require only a key to open. Higher security, such as the one belonging to the Lestrange family or the one belonging to the Potter family, requires not only the key, but also a goblin employee to lift the security measure around the door.