These printers use the C4195A cartridge:
Click On a Printer to View it's Cartridges
          HP Color LaserJet 4500
          HP Color LaserJet 4500 DN
          HP Color LaserJet 4500 HDN
          HP Color LaserJet 4500 N
          HP Color LaserJet 4500 Series
          HP Color LaserJet 4550
          HP Color LaserJet 4550 DN
          HP Color LaserJet 4550 HDN
          HP Color LaserJet 4550 N
          HP Color LaserJet 4550 Series
          HP LaserJet 4550 ODN