From Wanhao: The Duplicator 4S is the latest update to our Duplicator 4 series of printers. This printer comes with all of the great features of the Duplicator 4X (hinged safety door, two side safety panels, and a detachable hood) but has also been updated to include a steel exoframe, a steel printing platform, and a larger Z-Axis threaded rod. Other features include upgraded electronics and 1/16 micro-stepping motor control. Each printer Includes 2 filament rolls with 100 color combinations to choose from. This printer takes the Duplicator 4 to the next level!