Your little detective will enjoy using these markers that will allow for secret messaging and decoding action. See what you are writing and then watch it disappear. These markers feature special "spy" technology ink. A dual tip allows the messages to be decoded and then destroyed. The package comes with two non-toxicmarkers so children can share secrets with their friends. Use the colored tip to REVEAL your secret message once it has disappeared. Swipe each area once from left to right. Swipe the white tip over the message to destroy it forever.