Stillman & Birn Archival Quality Sketchbooks - Beta Series Wire Bound - This line of archival quality sketchbooks has a simple premise: When it comes to sketchbooks, paper matters! All of the books in this line are beautifully bound in the United States. The covers are extremely solid and the books literally feel different in your hands than sketchbooks made by other companies- these have a weight and sturdiness that you will notice right away. Made entirely out of archival materials, you will love these books. The Beta Series books are made with rough surface, 180lb natural white paper. This heavy duty paper is ideal for use with wet media and mixed media renderings. There are 25 sheets of paper per sketchbook.