Abstract: A system for dispensing imaging development material into a printer from a re-supplying container dispensing aperture sealed by a sealing plug, which plug is automatically unsealed by the insertion of the container into the printer, and automatically resealed by removal of the container. Simply pushing the container towards its normal position against the imaging material input of the printer (here, a fixed auger tube) first automatically grasps the plug in a gripping system and then pushes the gripped plug into the interior of the container while firmly holding the plug on the end of the auger tube. After the material dispensing, or whenever else the container is removed, simply pulling the container away causes the plug to automatically re-seal the dispensing aperture and then to automatically release the plug gripping system so that the re-sealed container can be cleanly removed.