Uncover a hidden world that s invisible in normal light with Nancy B s Science Club Black Light Illuminator & Nature s Mysteries Journal. Using the black light and invisible ink pen complete science-sleuthing activities such as observing rocks insects and flowers that glow under black light making gelatin that glows counterfeit money detection encrypting codes and ciphers and more. Includes a 22-page activity journal and black light illuminator invisible ink pen to write secret messages too! Requires 2 AA batteries (not included).