The revolutionary EnerGel pen contains an acid-free ink called Liquid Gel Ink, which combines the best qualities of both liquid ink and gel ink together, to create a pen with the smoothest writing feel ever. It also comes complete with a strong metal tip, a stylish silver barrel, a handy pocket clip and ink verification windows. Part of the Pentel Recycology range made from 53% recycled content for BL17 and 50% recycled content for BL60.