These printers use the C6615 cartridge:
Click On a Printer to View it's Cartridges
          HP Color Copier 310
          HP DeskJet 810 C
          HP DeskJet 812 C
          HP DeskJet 816 C
          HP DeskJet 825 C
          HP DeskJet 825 CVR
          HP DeskJet 840 C
          HP DeskJet 841 C
          HP DeskJet 842 C
          HP DeskJet 843 C
          HP DeskJet 843 CXE
          HP DeskJet 845 C
          HP DeskJet 845 CVR
          HP DeskJet 916 C
          HP DeskJet 920 C
          HP DeskJet 920 CVR
          HP DeskJet 920 CXI
          HP DeskJet 940 C
          HP DeskJet 940 CVR
          HP DeskJet 940 CW
          HP DeskJet 940 CXI
          HP DeskJet 948 C
          HP DeskJet 3810
          HP DeskJet 3816
          HP DeskJet 3820
          HP DeskJet 3820 V
          HP DeskJet 3820 W
          HP DeskJet 3822
          HP Digital Copier 310
          HP Digital Copier Printer 310
          HP FAX 1230
          HP FAX 1230 XI
          HP OfficeJet 5105
          HP OfficeJet 5110
          HP OfficeJet 5110 A21
          HP OfficeJet 5110 V
          HP OfficeJet 5110 XI
          HP OfficeJet V-30
          HP OfficeJet V-40
          HP OfficeJet V-40 XI
          HP OfficeJet V-45
          HP OfficeJet V
          HP Printer Scanner Copier 500
          HP Printer Scanner Copier 500 XI
          HP Printer Scanner Copier 720
          HP Printer Scanner Copier 750
          HP Printer Scanner Copier 750 All In One
          HP Printer Scanner Copier 750 XI
          HP Printer Scanner Copier 750 XI All In One
          HP Printer Scanner Copier 760
          HP Printer Scanner Copier 920
          HP Printer Scanner Copier 950
          HP Printer Scanner Copier 950 All In One
          HP Printer Scanner Copier 950 VR
          HP Printer Scanner Copier 950 VR All In One
          HP Printer Scanner Copier 950 XI
          HP Printer Scanner Copier 950 XI All In One