Deleting a slot
1. Open the Instance's Property Pages.
2. Click the Slot Values tab.
3. Select the Slot that you want to delete.
4. Click the 
Delete Slot button.
Delete Slot button.For a specification Slot, the Slot and its entry are deleted.
For a real Slot (one that has a Slot Value set), the Slot becomes a virtual Slot. Virtual Slots appear on the Slot Values tab, but they do not appear on Object Diagrams.
For virtual Slots, the Delete Slot button is not available.
Delete Slot button is not available.