Stillman & Birn Epsilon softcover sketchbooks are flexible, yet strong with sewn bindings and rounded edges. White, heavy weight 100lb paper has a smooth surface that is suitable for pen & ink, and dry media. The paper also has internal and surface sizing, allowing it to accept light washes as well. Paper is pH neutral, lignin and chloride free. Sketchbook measures 8.5 x 5.5 inches, Landscape format, with 46 sheets, dark gray cover.