GRAFWOOD is an 8-ply graphite pencil available in 15 gradations (4H - 9B). The diameter of the Grafwood cores varies. The harder grades have thinner cores for fine lines and the softer grades are thicker for sketching and shading. Generally, when you buy a Grafwood pencil you're getting 25% more materials than with a traditional pencil. Grafwood pencils have a maximum diameter of 8.20 mm. Our 9B pencil offers the consumer the softest and blackest graphite on the market. When an artist begins using the full range of Caran d'Ache graphite gradations they quickly learn to appreciate the silky smooth texture.