OfficeSmartLabels ZT400300 Ribbon Required 4 x 3 Inch Thermal Transfer Labels Compatible with Zebra (20 Rolls, White, 500 Labels Per Roll, 1 inch Core) 20 Rolls / 1" Core / 500 Labels Per Roll Top Coasted with Moisture & Oil Barrier / Ribbon Required Direct Thermal / Rounded Corners / Perforations Between Each Label Compatible with most Direct Thermal Printers including "Zebra", "Eltron", "Datamax", "Intermac", "SATO"and "Fargo" OfficeSmartLabels does not sell Zebra/Eltron branded labels. "Zebra", "Eltron", "Datamax", "Intermac", "SATO"and "Fargo" and other related branded product names and SKU trademarks are trademarks of their respective owners and not OfficeSmartLabels. Neither Zebra/Eltron nor any of the other printer companies mentioned above sponsor or endorse any products made or sold by OfficeSmartLabels.