ZyXEL Communications P-2802H(W)(L)-I Series - Manual (Page 169)

Chapter 11 Firewalls
P-2802H(W)(L)-I Series User’s Guide
169
Figure 95 Firewall Example: Edit Rule: Destination Address
9 Use the Add >> and Remove buttons between Available Services and Selected
Services list boxes to configure it as follows. Click Apply when you are done.
"
Custom services show up with an “*” before their names in the Services list
box and the Rules list box.