There are several features that make OPOLO Cosmos secure. OPOLO Cosmos uses a Secure Element (SE) that has CC EAL6+ certification and was developed by one of the major semiconductor companies, NXP. No sensitive data like mnemonic or private key ever leaves the OPOLO Cosmos device. The passphrase is never stored on the device. The password is stored only in the Secure Element. The wallet mnemonics are stored only in the Secure Element when the device is powered off. The password and passphrase are entered directly onto the device to avoid the chances of them being compromised if the computer is infected by some malware. The password and passphrase can be as long as 120 characters long, not supported by any other wallet in the market. The firmware is signed with OPOLO keys and encrypted when installed. The PCBs are potted with chemicals, making it very difficult to tamper.