There are two removable media which work as keys: the auth key and the panic key. The auth key will let you pass to the password prompt whereas the panic key, if provided, will securely erase the LUKS header, rendering the data unreadable.
### Using two passwords previous your own password
There are two passwords you are able to set: the key password and the panic password. The key password will let you pass to the original password prompt whereas the panic password, if provided, will securely erase the LUKS header, rendering the data unreadable.
You'll need two GPT-formatted removable storage devices, and said devices must have at least one partition. Here's an example `fdisk` session, showing how this might be accomplished:
You'll find the UUID of your partition in `/dev/disk/by-partuuid/`. You can find out which device is which typing `ls -l /dev/disk/by-partuuid/` in your favourite shell.