The User-Defined tab is only visible if you have defined one or more user-defined fields in the AP Module Preferences window on the User-Defined Fields tab.

If you defined any of the fields in Module Preferences, the fields you defined will appear here, with the captions you entered in Module Preferences. If many of your vendors will use the same information in any of the User-Defined Fields, you can enter that information in this template to set the default for new vendors.