Genuine Lexmark Supplies are engineered to work best Together with your Lexmark printer, delivering excellent print quality from the first page to the last. Lexmark offers customers a broad choice of laser toner cartridges and recycling options including Easy return to Lexmark. For superior results, always use genuine Lexmark Supplies. Essential to Lexmark print system performance, unison Toner's unique formulation consistently delivers outstanding image quality, ensures long-life print system reliability and promotes superior sustainability -- all in an innovative shake-free Print system. Includes high yield print cartridges 20N1HK0 black, 20N1HC0 cyan, 20N1HM0 magenta and 20N1HY0 yellow Set yields up to 4, 500 pages. For use with Lexmark CS331dw and CX331adwe color laser devices.