These printers use the 50F0UA0 cartridge:
Click On a Printer to View it's Cartridges
          Lexmark MS 312 DNW
          Lexmark MS 510 DN
          Lexmark MS 610 DE
          Lexmark MS 610 DN
          Lexmark MS 610 DTE
          Lexmark MS 610 DTN
          Lexmark MX 611 DFE