The Kaweco Perkeo M transparent fountain pen set with 3 refills allows you to see the entire internal mechanism and ink level through its translucent body. Measuring 14 cm in length and made of transparent plastic in a demonstrator style, it features an ergonomic triangular grip, a medium M stainless steel nib, and an octagonal snap-on cap. The package includes 3 universal royal blue ink cartridges, which can be used with any colored ink or standard converter for a unique visual effect. The transparent, colorless finish is the ideal choice for those curious about writing mechanics and for practical school use.