Genuine Lexmark supplies are engineered to work Best Together with your Lexmark printer, delivering excellent print quality from the first page to the last Cartridge yields up to 15K pages Compatible with Lexmark MS821n, MS821dn, MS821de devices Essential to Lexmark print system performance, Unison Toner's unique formulation consistently delivers outstanding image quality High yield cartridges offer a lower cost per page and contain more pages than standard yield cartridges do