Pentel Fountain Pens have a marbled barrel and come with black ink. They are perfect for a variety of uses. The ink is water-based and the Delta nib has two very different sides. One side of the nib is firm and is ideal for sharp lines and the other side is softer and more pliable, making it a great pen for Calligraphy and other fluid stroke work.
The line width can be varied by applying different amounts of pressure to the two corresponding sides. As this pen is disposable, there is no need for messy refilling. Available in black ink.