The FriXion rollerball pen has a unique gel ink that responds to the heat generated by the eraser, allowing mistakes to be written over immediately with the same pen. Ideal for home or in the office, it offers a comfortable hold with its ergonomic grip and features a handy clip on the lid for attaching it to papers and notebooks while out and about. Refillable for economy and long lasting use, the FriXion rollerball has a medium 0.7mm tip for precise lines and smooth, fluid writing. This pack contains 12 pens, plus 12 refills.