Cisco – Interpret the Serial Number

The serial number is defined as such:

  • FAA—Flextronics, San Jose, CA. (Depending on the manufacturer, these first three digits can vary.)
  • NN—The number of years Flextronics has been a Cisco supplier. (For products built in year 2004, the number is 07.)
  • NN—The week number the product was built.
  • XXXX —A unique identifier.



From :

Do a “show inv” that will show you the serial number.

The serial number looks like this:

The ABC represents the manufacturer/assembler of the part.
The 00 represents the year it was made, starting with 00 for 1997, 01 for 1998, etc.
The 11 represents the week it was made.
A1B1 is the unique portion of the serial number.