Crafted from PP, this invisible marker set smooth writing and LED light for long time use Suitable for children, adult, students, teacher, professional, and anyone who needing discreet document marking or creative art craft project requiring secret annotations secure and fun invisible writing with our Invisible Inks Pen and LED Light Set, featuring 2 invisible marker pen and LED flashlight keychain for revealing secret messages instantly Transform ordinary note into exciting discovery with this invisible marker that combines practical informations security with engaging LED revealing creativity Widely used for kids birthday, party game, baby showers, school assignments, confidential file labeling, and interactive family activity using LED reactive secret messaging