The OnlyKey can hold 24 unique accounts including username, password and two factor authentication. It is PIN protected with a 7 to 10 digit pin utilizing strong symmetric encryption. It is compatible with everything as it is only seen as a keyboard for user account logins. OnlyKey is OpenPGP compatible, so signing and encrypting messages and decrypting and verifying messages is possible with the OnlyKey using both RSA and ECC asymmetric encryption ciphers. Basically, it is a hardware password manager.