For multi-shade 3D printing, a regular twin extruder 3D printer, one which includes a one mount for the dual nozzles, is adequate. But don’t assume it to be as speedy as one extruder 3D printer, taking into consideration the additional excess weight to the print head influences the print velocity. https://paxtonyrgwn.thelateblog.com/30227024/little-known-facts-about-multicolored-3d-printer