Laser printers are recommended for printing labels. Ink jet printers should not be used because of their inconsistency in creating scannable barcodes. Due to the inconsistent print quality, the label certification teams reject most labels that are created with ink jet printers. The 4" x 6" PNG label cannot be printed using a color printer unless the color definition is set to black, even if the printer only has a black cartridge installed. This setting is necessary to achieve the correct barcode definition for scanning at the FedEx hubs.