Difference between M66FB-03-STD and M66FB-04-STD

Hi everyone,

I have a question,what is the difference between M66FB-03-STD and M66FB-04-STD? Couldn’t find any doc about it.

Thanks!

these two type is compatible PIn to PIN , but up to now ,M66FB-03-STD is plan to phase out

pls using 04