The Pilot FriXion Gel Pen (PIL31550) features erasable gel ink that allows you to write, erase, and rewrite without damaging documents. Its thermosensitive ink formula disappears with the friction of the rubber plug eraser on the pen, leaving no residue or debris. This gel pen delivers smooth writing but is not recommended for use in extreme temperatures or for signatures and official documents where permanence is required. The FriXion Gel Pen has also earned the prestigious Good Housekeeping Seal.