Agilent Technologies 8564EC Service Manual page 22

General Information
Serial Numbers and Repair Information
Figure 1-2 Earlier Serial Number Label Example
It is important that you realize that the new serial number format
(US00000000) is always considered "above" the earlier format
(0000A00000) when you encounter change information such as
"....serial prefix 3425A and above" or "....serial number 3425A00564
and above."
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