otp slotThe YubiKey's OTP application slots can be protected by a six-byte access code. Once a slot is confured with an access code, that slot cannot be reconfured in any way unless the correctDuring manufacturing, YubiKeys are confured with a Yubico OTP (in the short-press slot), and the OTP secrets are uploaded to YubiCloud. This enables out-of-the-box OTP authentication.