Copic Marker Nibs styles of COPIC interchangeable nibs - from broad to calligraphy - provide greater freedom of technique in your renderings. - The nibs are made of a strong, but flexible polyester for smooth, consistent application. - When a nib wears out or a different style stroke from the pen is desired, simply replace/interchange the nibs - NO need to buy a new pen! Optional nibs, comes with identification stickers.