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.