Are you still using regular colored pens to draw wavy lines? Try this specially designed roller marker pen. With just a gentle pull, you can create various exquisite and perfect marking lines without any other help, making them simple and perfect. Dual tip design with a roller end for marking lines and a 0.5mm thin pen tip for writing, detailing, and drawing. Combining them will give you a great learning and artistic tool. [Durable] The ink level of the upgraded gel highlighter has increased by 40%. The marking line is longer than before and can be used for a longer period of time. The pen tip adopts a new type of non drying ink, which can maintain even ink and smooth writing even if you forget to cover the pen tip again, perfectly solving the problem of most fountain pens with dry ink. Safe and High Performance Fluorescent pens are acid free, non-toxic, ink resistant, durable, and do not fade. It is safe for students or children. This set of multi-color highlighters allows all children to smoothly apply it to card making, arts and crafts, book coloring, DIY letters, and more. This cool set of markers can be a great gift for children to express their imagination, or a great gift for adults who love DIY as a popular gift. Making perfect marks is no longer a daunting task.