property Items.ItemHeight(Item as HITEM) as Long

Retrieves or sets the item's height.

TypeDescription
Item as HITEM A long expression that indicates the item's handle.
Long A long value that indicates the item's height in pixels.

To change the default height of the item before inserting items to collection you can call DefaultItemHeight property of the group. The control supports items with different heights. When an item hosts an ActiveX control ( was previously created by the InsertControlItem property ), the ItemHeight property changes the height of contained ActiveX control. Also, please check the CellSingleLine property.