For high yield printing purposes with quality and reliability from your Kyocera FS-4000DN printer, install a genuine Kyocera Black Laser Toner Kit (TK330). Order a new toner kit when your printer displays a Toner Low error message and keep it handy. When the current toner cartridge is exhausted, the printer will display Replace Toner and you must install a new cartridge before resuming printing. This extra high yield cartridge is packed with more black toner - enough to print 20,000 pages.