The Daler-Rowney Ebony Portrait Spiral Sketchbooks feature a selection of artists’ black cover spiral sketchbooks with premium quality, crisp, white cartridge paper suitable for all dry techniques and pen & ink work. Quality/Recommended: Recommended for professional artists and art students. Weight: 160gsm Acid free: Yes Made from: 100% alpha cellulose offering the purest cellulose, highest quality. Colour: White Ideal for: Ideal for dry techniques as well as pen and ink. Texture: Smooth Brand: Daler-Rowney Format (cm): 21 x 14.8 cm (A5), 21 x 29.7cm (A4) & 29.7 x 42cm (A3)  Format (inches): 8.2 x 5.8 inches (A5), 8.3 x 11.7 inches (A4) & 11.5 x 16.5 inches (A3) (approx.) Sizing: Internally sized. Mould made: Made using a Fourdrinier Machine. A technique from the 19th century, allowing constant quality of the paper.