HP Color LaserJet CM4730 MFP - Software Technical Reference (external)
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... print modes when you are using media that is set to its print modes. To make the Print on the Duplex Unit (for HP Color LaserJet CM4730MFP models that has the best possible quality for Windows ENWW Finishing tab features 145 This group of the media for 2-Sided Printing)... as fuser temperature and print speed) to print on the second side of settings is enabled in the driver, the MFP automatically prints on both sides of media types that are supported for automatic duplexing (Letter, A4, Legal, and 8.5 x 13 only), and forces manual printing on all HP Color LaserJet CM4730MFP ...
... print modes when you are using media that is set to its print modes. To make the Print on the Duplex Unit (for HP Color LaserJet CM4730MFP models that has the best possible quality for Windows ENWW Finishing tab features 145 This group of the media for 2-Sided Printing)... as fuser temperature and print speed) to print on the second side of settings is enabled in the driver, the MFP automatically prints on both sides of media types that are supported for automatic duplexing (Letter, A4, Legal, and 8.5 x 13 only), and forces manual printing on all HP Color LaserJet CM4730MFP ...