The external serial EEPROM provides the possibility to customize the USB identity for each product. The OEM makers could make products for different customers by just putting the vendor/product ID and names in the EEPROM but still keep other things the same. The serial number can help the system manufacturers to track down every single device they made even when the design and the PID/VID are all the same. The USB Mass Storage Class compliance capability of SN11012 makes it a truly "plug-and-play" device without vendor drivers needed under the OS like Windows 2000/ME/XP and Mac OS 9/10. This feature not only makes the system developing faster and easier, but also reduces the cost and increases the reliability. The SN11012 even provides the capability to boot the PC. Therefore, the system manufacturers can use it to build a much faster, high capacity, reliable, and portable system to replace the legacy floppy disk easily. 1