This pack of 3 Frixion Erasable Rollerball is a unique set of pens with ink that can be erased. This pack of erasable 0.7mm pens include in, which erases by friction-generated heat. Just rub rapidly, using the end stud on the pen barrel, or a similar material.This set would be ideal for writing notes in diaries and or for your Sudoku\'s (not on newspapers).. No eraser debris or glossing of the paper. No chemicals needed to erase. Erases cleanly. Same ink writes and over writes. All in one pen!