Pilot Parallel Calligraphy Pen Set, 1.5 mm, 2.4 mm, 3.8 mm and 6 mm with Bonus Ink Cartridge (P9005SET) Unique parallel plate structure achieves a more beautiful and sharper handwriting than existing calligraphy pens. Mixable colors - using two Pilot Parallel Pens each with different color cartridges produce beautifully gradated lettering by touching the nibs together Each set comes with 4 Parallel pens: Available in 4 nib sizes: 1.5mm (Red Cap) 2.4mm (Orange Cap) .38mm (Green Cap) and 6.0mm (Blue Cap)