This Staedtler 3004 wallet contains 12 double-ended lettering pens with a flexible brush tip and a fine tip. It is made for hand lettering, calligraphy, bullet journaling, illustration, manga, and coloring. The brush tip writes at about 1.0 to 6.0 mm, while the fine tip is about 0.5 to 0.8 mm. The assorted ink colors support varied lettering styles and tip-to-tip blending. The pen bodies and caps are vented polypropylene, in line with ISO 11540.