Perfect for navigation, taking notes about a dive spot, documenting coral reef growth, or just for communicating to your dive partner. The best part is that at the end of the day just clean it off and you can use it again and again. Underwater Writing Notepad for Snorkeling, Scuba Diving to Tell your dive buddy what you are seeing by simply writing on the face of this easy to use underwater communication device. Great item for communicating underwater, especially for trainers.