HP LaserJet C3903 Family Print Cartridges is compatible with the following products:
HP LaserJet 5mp Printer (C3155A) HP LaserJet 5p Printer (C3150A) HP LaserJet 6mp Printer (C3982A) HP LaserJet 6p Printer (C3980A) HP LaserJet 6p se Printer (C4212A) HP LaserJet 6p xi Printer (C4213A)