For a period of time Ultimaker have started preparing the Ultimaker Original for Dual Extrusion, and have put extra holes for this upgrade in the backplate. An exact copy of the holes where the current feeder is mounted. However the older machines don’t have these extra holes, and will need a printable add-on, we call ‘Mounting Aid’. Please make a selection in the menu whether you are in need of the Mounting Aid, or if your backplate is prepared. The Mounting Aid is also available on YouMagine.