The "professional's" Bound Book - the only books manufactured with true outdoor durable components. The cover, the paper, the sewn-in pages, even the glue is designed to survive the elements. This is a PolyDura Hard Bound Field book with 4 3/4" x 7 1/2" sewn pages. Polydura covers are a smooth plastic material made with post-consumer waste. They're virtually indestructible.