If you want to refill these cartridges you need a chip resetter, which will reset the chip on your existing cartridge, and make it register as 'full' to your printer.  It works with BOTH your black and color cartridges and you can use it up to 1,000 times (actually you can use it forever if you replace the little watch batteries inside the unit).   We have this cost-saving tool available for $24.95, which makes refilling a breeze.