[Eddies66]

From the PACT Act:

To get a VA disability rating, your disability
must connect to your military service. For
many health conditions, you need to prove
that your service caused your condition.
But for some conditions, we automatically
assume (or “presume”) that your service
caused your condition. We call these
“presumptive conditions.” We consider a
condition presumptive when it's
established by law or regulation. If you
have a presumptive condition, you don’t
need to prove that your service caused
the condition. You only need to meet the
service requirements for the presumption.

There are 23 presumptive conditions listed.