FriXion Ball is a revolutionary ballpoint pen that can be erased The long-awaited retractable friction ball is finally here! The long-awaited retractable friction ball is finally here! Can be used quickly to write notebooks and documents. Knock is done with a clip slide knock The small window shows the "ON" state (knock indicator). [Features] ◆ Introducing a retractable friction ball. Uses a unique FriXion ink that disappears when temperatures exceed a certain temperature. Rub the ink to make it clear The ink makes it colorless by using temperature changes, so it does not leave erasing. Can be written and erased repeatedly. ◆The main unit has a matte finish and has a simple and stylish design.