Pilot Frixion erasable stamps use the magical Frixion erasable ink (thermo-sensitive ink). They are your best tool to mark events in your planner or calendar. Frixion ink allows you for easily making changes when you make a mistake or your plans change. Just wait for the ink to dry and then erase the stamp using the special rubber "eraser" at the back end of the stamp. The ink will disappear cleanly without creating any dust or smearing so that your calendar or planner will always stay clean.