Pen Mil-Tec of type rollerball, with blue ink. Rollerball pens have a writing similar to that of a fountain pen. They produce the most ink compared to other types, have comfortable writing, do not skip, but may smudge. Not recommended for low-quality paper and left-handed individuals. The ink lasts less compared to ballpoint and gel types. It features a sturdy and sharp construction that can be used for self-defense purposes.