This converter allows you to draw ink from an ink bottle into your fountain pen. A favorite by many for its large ink capacity. Make sure this converter is compatible with your pilot pen before purchasing. It may be too large to fit in some slimmer models like the E95s. 

To use the converter attach to the front nib section of your pen. Submerge your nib in the ink bottle and give the converter about 5 quick pumps. The quicker the better fill you will get. I like to keep a tissue or paper towel near by to wipe away any excess ink once I'm done.