What is "port sets" screen used for?

In CIS, there is a screen called “port sets”(Firewall>NetworkSecurityPolicy>Port Sets) – Can I use CIS to block any member of the individual port sets shown at this screen, or just what is it used for?

For instance, if I “Exclude” port 25 from the “POP3/SMPT” default listings, will this port then be blocked?

Also, If I click on the “POP3/SMPT” heading and then click on “Remove”, then will all POP3/SMPT ports (as listed underneath that heading) be blocked?

Thanks for any help you can me give on this. Trying to block a botnet or trojan that could be using these ports, and cant get antivirus or antispyware to detect it. (I am using cloud-based e-mail so dont use these particular ports).

The 'Port Sets" configuration screen simply makes it easy to add a group of ports that can be used when creating firewall rules.

Taking the POP3/SMTP Ports as an example, this group contains ports typically used by email programs. So, when you configure a firewall rule for your email client, you can use the port set definition in the rule, as opposed to listing the ports individually.

The port sets are also used in the pre-defined policies. If the port sets are not used in a rule they have no effect on the firewall, likewise the Network zones.

mod edit: typo corrected by Mod. kail