Ergonomically designed with a non-slip surface over their entire shaft, these easy-to-grip pens features high quality 0.5mm nickel rollerball tips for extremely smooth writing. They utilize the latest bionic liquid ink technology. The colored shafts indicate the color ink in the pens. Ideal for professionals and frequent users, their design allows for relaxed fatigue-free writing. Details:Available in multiple colors0.5mm rollerball tipBionic liquid ink