If you like to write thin then the Pilot G-Tec C4 is the pen you need. Pilot Gtec C4 has a ball diameter of 0.4mm and a stroke width of 0.2mm. The Pilot Gtec c4 is ideal for small phone books, mini journals and much more . The pilot gtec c4 is also great for art. Some will use the G-tec for every day writing saying these pen make my handwriting stunning.