Write, erase, and write again! The roller pen has a plastic body and thermosensitive archival-safe erasable ink, not intended for official documents and for signing checks. The tungsten carbide ball with a diameter of 0.7 mm is housed in a... sturdy steel tip, providing a consistent line width of 0.5 mm and a length of up to 250 m. The ink dries in 15 seconds on most types of paper. Attention! Only after the ink has dried can the writing be erased using the pen cap and the end of the body as an eraser.