When using the Business or Pro-Smart editions, this tab contains all of the Mifare® DESFire read items that have been defined.
Simply select the item and drag and drop it on your card design.
You can also select Mifare® DESFire read items as sources for other objects such as Storage items by selecting them from the drop down of available sources in the properties window.
How to configure Mifare® DESFire read items is explained in the "Mifare® DESFire" section of this Help file.