Cryptosteel is a fireproof, shocking and waterproof device for Bitvoin holders. It provides Bitcoin owners with a perfect backup plan for private keys. Cryptosteel promises added security. It complements other hardware wallets. For multisig addresses, users can back up their Bitcoin addresses in different Cryptosteel devices and place them in different locations. Cryptosteel can also be used to back up hardware wallets like Trezor.