Custom Fields can be used to store additional information for Service Plans. Your User Group Permissions determine whether or not you have the ability to manage these settings.
There are 20 customizable fields available to you: five Text fields (limit of 300 characters), five Date fields, five Boolean (Yes/No), and five List fields where you can customize a drop-down list.
Here you can choose to add Custom Fields to your list. The dropdown will display each type of Custom Field and indicate how many are already in use and how many are available. You can also edit existing or remove existing Custom Fields.
You can move them up and down in the list as to your preference:
For "List" Custom Fields you will manage the list via the Manage button:
The following dialog will open that allows you to add/edit/delete items to the list. You can also use the Move Up/Down buttons to choose the order of the items in the list and set the case.