Remanufactured Ink Cartridge Replacement for HP 21 (1 Black 1 Pack) Alternative to OEM, comes with ONE YEAR WARRANTY from the date of purchase against manufacturer defects. Page Yield: Black 190 pages at 5% coverage on Letter/A4 paper. This replacement Inkjet cartridge is built to ISO9001 and ISO14001 Factory Standards. Compatible with Deskjet 3930 series Deskjet 3940 series PSC 1410 series