Ergonomically designed with a sleek black non-slip surface over the entire shaft, these easy-to-grip pen sets feature high quality .3mm fine and .5mm medium nickel silver rollerball tips for smooth writing. Bionic Bl@ck pens utilize bionic liquid ink technology and are available in six ink colors, red, blue, black, green, turquoise and lilac. Ideal for professionals and frequent users, the unique design allows for relaxed fatigue-free writing.