4 vivid metallic colors, suitable for opaque writing, decoration, graffiti, painting or coloring, even on dark and colored paper. Each metallic color is very attractive, adding creativity and to the items. Due to the metallic luster of the ink, the letters and marks produced will be both obvious and eye-catching.Built-in ultraviolet light, children will write a lot of secret messages to each other, the ultraviolet light will appear on the if it is invisible to the eyeNote: You can write on most surfaces, but whether it can stay on the surface depends on the type of material you write. If you write on paper, it can stay forever; if you write on metal or plastic, it may not last long because it can be easily erased due to the properties of metal and plastic.Great party bag stuffed toys for boys and girls for kids.colour: as shownMaterial: plasticPackage Contents:4 x invisible ink pen(green, blue, yellow, pink)Only the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.