These cards are for use with inkjet printers that have a PVC card tray (sold separately). You can print on both sides of these cards and these are the only cards that should be used in an inkjet printer (normal PVC cards will not absorb normal ink from an inkjet printer). Using these cards and the PVC card tray in your inkjet printer is a great alternative to the much more expensive dedicated ID Card Printers made by Zebra, Fargo, DataCard, Evolis, Magicard, etc.