USB Key Security Device FTDI USB Key Security Device has a unique identification number burned into it during manufacture. This FTDIChip-ID™ number is only readable over the USB interface making it an ideal key for unlocking particular applications. The FTDI USB Key features a simple to use the USB interface to any USB host or hub. The unique FTDIChip-ID number can be used to provide a security dongle for software applications. Additional security is possible by encrypting the FTDIChip-ID number and storing it in the EEPROM writeable area of the FTDI USB Key.