With the HP 90X Black High Yield LaserJet Toner Cartridge providing the very highest level of clarity, you can be sure that everything you print will have a professional quality that is unbeatable. HP designs its cartridges to work perfectly in its machines, freeing you from the stress that comes with trying to mend your printer. Featuring a high page yield, this cartridge is ideal for use in a high volume situation, for example in a busy office. Each cartridge is easily installed into your printer, providing you with great results from the first print. Please note that this item is compatible only with the Enterprise M4555 series and Enterprise 600 M602, M603 series printers. (not M601).