HouseOfToners Remanufactured Ink Cartridge Replacement for HP 21 C9351AN (4 Black, 4-Pack) All cartridges have undergone extensive cleaning, been re-filled to OEM capacity, and tested to ensure quality and compatibility (please note per Magnuson-Moss Warranty Act, using remanufactured cartridges will not void your printers warranty) Contents: 4PK HP 21 (C9351AN) Black Ink Cartridges Page Yield: 190 pages (page yield measured at 5% page cover of standard 8.5x11 sheet) | Shelf Life: 12-18 Months We ship within 1 business day via USPS First Class, USPS Priority, or UPS Ground 100% Satisfaction Guaranteed with 1-year replacement policy