It writes with invisible ink made of special high-brightness ultraviolet visible compounds
This means the ink is completely invisible under normal light
Near the visible spectrum of light. Flip the pen over, shine the light on the spot where the ink was used and your hidden message will be illuminated
You can use it in various and amusing occasions: secret messages, invisible tattoos, fantastic drawing in the darkness, personalized objects, highlighter and anti-counterfeiting etc.
Package includes 6 * LR41 button batteries