property Items.ItemData(Index as Long) as Variant
Retrieves or sets a value that indicates the extra data for a specific item.

TypeDescription
Index as Long A long expression that indicates the index of the item.
Variant A VARIANT expression that indicates the item's extra data
Use the ItemData property to assign an extra value to an item. Use CellData property to associate an extra data with a cell. The ItemData and CellData are of Variant type, so you will be able to save here what ever you want: numbers, objects, strings, and so on. The user data is only for user use. The control doesn't use this value. Use the Data property to assign an extra data to a column. For instance, you can use the RemoveItem event to release any extra data that is associated to the item. Use the FindItemData property to search for item's data.