The Paste Special option within Visio and AutoCAD and allows you to choose whether or not Products will be added to the Project when you copy/paste from one Visio/AutoCAD page/drawing to another page/drawing.
Paste Special allows you to choose the behavior of pasted shapes.
In the D-Tools Right-Click menu, there is a Paste Special option within both the Visio and AutoCAD interfaces when you have copied shapes/blocks:
This will open the following dialog with three options: