Field-Flex is our most flexible cover material. The paper-based stock is tough enough to withstand the harshest and wettest conditions yet can be torn like heavy paper. As its paper-based, it can be recycled with other papers. Perfect bound books are made by grinding the ends off folded sheets (called signatures) then gluing them to a cover stock. Our perfect bound books use only the most durable glues to ensure your Rite in the Rain book won't fall apart in the field. As with most perfect bound books, the text sheet edges are flush with the cover. We take the extra step of round-cornering our books. This improves durability and protects you from annoying sharp corners. The handy Pocket-Sized Field-Flex Books are great for stowing in tight spots but still large enough to take all your vitals whether it be an landmark, coordinates, animal sighting or a phone number, you can trust these little notebooks with the information you gather.