About this 3D model

You will need to print the ring and the top unit and glue them together. The design allows you to reverse the ring so the super smooth surfaces of the print bed are what should be glued together. I decided to go with the ring design to remove any need for bridging, allowing for a cleaner print. If the switch plate you are using this on is recessed into the wall, you will not need the ring, but I have found most seem to be raised slightly and space is required behind the plate to allow it to set cleanly on the wall.