MITSUBISHI PENCIL Oil-based Ballpoint Pen Jetstream Color Ink (0.5mm / 0.7mm) 1 pc The ultra-smooth colored ink is convenient for color-coding notebooks. Jetstream differs significantly from conventional oil-based ballpoint pens in its smooth writing feel and quick-drying performance, enabling clear, dark lines to be drawn smoothly and glidingly. The spring tip and twin balls built into the nib prevent backflow and excessive leakage of ink, which are common problems with conventional oil-based ballpoint pens, making this a ballpoint pen that is pleasant to use all the way through. The fact that it comes with a body clip to prevent loss in pockets, bags, or on desks is another secret to its popularity.