The image shows the content present in the "Trusted Add-in Catalogs" menu.
In the right side of the pane, there is a Catalog Url field.
There is an "Add Catalog" button to the right og the Catalog Url field.
Below the Catalog Url field, there is a table which consists of the "Trusted Catalog address" column, "Catalog Type" and the "Show in Menu" check-box.