The TN3430 toner cartridge has been produced by Brother to their own exacting standard and is of incredibly high quality. Original toner cartridges are filled with the powder that your printer was designed to use and made of the components it was meant to interest with, as such there is no better choice for your printer than cartridges like this. This genuine original Brother black toner cartridge offers an estimated 3000 prints and is fully guaranteed to work with the Brother MFC-L6900DWT and all of the other mono laser printers listed on this page.