Zebra dispenser upgrade kit P1112640-031 adds a front-bezel dispenser to a compatible label printer. It is listed for the Zebra ZD421D and ZD621D, so the part’s purpose is clear: it supports dispensing labels as they are used.
The dispenser automatically separates each label from its liner. This makes labels available without their backing material and helps minimize jamming around the platen roller. The item is supplied as a kit; the listing does not specify additional package contents.