The Insight Rollerball pens have a stainless steel tip that writes smoothly with very little pressure needing to be applied. These pens are ideal for everyday use in the office, home or school, as well as taking notes, revision notes or writing up assignments. The gel ink gives a smoother writing performance with no skipping or blobbing. All of the pens in this pack contain uni Super Ink. Uni Super Ink provides super resistance, resilience, speed, legibility & colour that lasts. But how does uni Super Ink defy crime & time? It"s all down to larger particles of ink with super strong chemical bonds, for long-term resistance to even the toughest elements. When exposed to UV light, water, alcohol or absorbant paper, uni Super Ink holds fast, ensuring vivid & bright colour that stands the test of time, & even resists the solvents used by cheque & document fraudsters