Dowel Center Transfer Plug

This plastic plug + a tree screw allow to transfer dowel hole center from one part to another part. These plugs are for 6 mm, 8 mm and 12 mm dowels. You will need 3.2-4.5 mm diameter screws depending on plug size. My original idea was to use screws of a particular length, so that screw's head would rest at the bottom of the hole. But I can see now that the screw sits tight enough in the plastic alone, so the screw can leave the center mark without any issues (without sliding inside the plastic plug).