The part number should be visible via this link:
But they forgot to add the "Ordering and Compliance" link as shown in the example below.
Intel seems to forgot to add this information for the S4500, S4600 and P4600 series.
Unless they add this info, I can't tell what the part numbers are.
This message was posted on behalf of Intel Corporation
Just like LFM mentioned above, it looks the Ordering and Compliance section of the ARK link is missing. We will be reporting this situation right away so you can access to that section.
We will keep you posted over here.