Specification :Color: SilverWith invisible ink and ultraviolet， creative and interestingOpen the UV light to point at the words you write and you can see them clearlyAble to write on paper， body， wall， pathetic， wood product， metal product， cloth， etc.Powered by 3 x AG3 cells (Included)Dimension: 135 x 14 mm / 5.31 x 0.55 inchApplication: Secret messages， invisible tattoos， fantastic drawing in the darkness， perfect secret， personalized objects， highlighter， anti-counterfeitingPackage includes :3 x 2 in 1 Invisible Ink Pen with UV Light