Write down your diagnosis in this cute Doc McStuffins Electronic Secret diary. Use the magical pen to write down all your secrets and close the Diary to keep them safe; If you want to read the secret messages, open the diary up using the special electronic key fob and shine the key fob light onto the message to make it appear. Dont worry, no one else will be able to sneak a peek at your secrets, the diarys alarm will activate when anyone but you tries. Alarmed diary prevents intruders. Invisible ink pen and a key fob with ultraviolet light. For ages 3 years and over. AAA 9V (included) . WARNING(S): Not suitable for children under 3 years old. Only for domestic use. This product contains no.