Ever been scuba diving and didn’t have a guidebook to figure out what kind of fish you were looking at?

Well, the folks at ByoGuides have a book you can take underwater called the “Reef Finder.”

It’s a visually driven, plain-language, ocean-literacy tool that reverse-engineers the “What is that?” question in favor of the user.

The reader can put any common reef dwelling fish or invertebrate into a “group,” and then the book gives the diver the most useful common name and visual characteristics to confirm the ID via post-dive look-up and learning using traditional topside field guides or resources.

The book uses visual logic instead of technical words and abstract concepts. The diver can search a nine-page “Visual Index” using common shapes like “spirals,” “sausages,” “threads,” “ribbons,” “fans,” and others.

The “Reef Finder” also has categories like “shapes,” “holes,” “tentacles,” and even “sediments.”

The book retails for US$36.95/33.78 Euros. For more info, check out the ByoGuides website or watch the video below.

‘Reef Finder’ underwater guide book