Perfect for use in your work books and pedigree charts. The erasable Frixion Ball is a unique gel pen, perfect for everyday use at work, home or school. With no damage to the paper, you can erase and instantly re-write over your mistakes. The friction generated heat caused when rubbing the paper with the special tip turns the ink invisible. Product Features • Erasable gel pen • Perfect for everyday use at work, home or school • Friction generated heat turns ink invisible Note: Do not use Frixion Ball on legal documents, cheques or when writing exams.