Write Your Secret Message - This magical invisible ink pen will write your secret message When your secret message is written with this invisible ink pen, wait a few seconds for the light from the pen's cap to illuminate and reveal the hidden message Spy equipment for children Widely used - Harmless and odorless ink, healthy toy for your kids Evenly and colorfully invisible ink on t-shirts, paper, skin, and all surfaces Permanent but washable You can easily create a fun gift for a child's birthday party, gift ideas, treasure hunt, escape room, or classroom activity with invisible ink clues Perfect Gift for Fun Parties - This invisible spy pen comes in a package of 7 and can write your secret message on the label Parents can buy it for their children's party at home Children love using this type of pen to keep their secrets and play detective spy games Schools, teachers can buy it for students for a school activity Add it to any surprise gift or as a filler gift for children Package contains - 7 invisible magical pens with built-in UV lamps Batteries included and installed They all have a pull tab to save battery life Pens will come in different colors to keep the activity exciting Caution: For children over 3 years old We consider our customers our highest priority Contact us if there are any issues (Note: The visible ultraviolet light appears as blue-violet)