Wiping principle: The rough abrasive particles of the eraser rub off rubber particles. By damaging the surface of the paper, the writing is carried away. It is not recommended for use on thin paper. The bevel design allows for easy wiping of details with less effort. It can erase various types of writing, including that from fountain pens, gel pens, ballpoint pens, and pencils. There are two options available: one is fully abrasive and the other is semi - abrasive