Installing a genuine HP 90A LaserJet Toner Cartridge ensures exceptional quality and reliability from your HP LaserJet printer. This cartridge uses high quality toner that gives you crisp text and detailed monochrome images across a range of applications, including letters, presentations and brochures. Because it's a genuine HP cartridge, it ensures unbeatable reliability and efficiency - giving you fast, trouble-free print operations. This cartridge is compatible with the HP LaserJet M4555 Series, M601, M602 and M603.