Graphite pencils help to add depth and shading to your sketch. Perfect harmony between the various hardnesses is important for this. The graphite core of a Bruynzeel Expression pencil measures between 2.2 mm and 3.5 mm in diameter (depending on the hardness). Bruynzeel Expression series of graphite pencils are available in a tin of 12 pencils. The comprehensive set comprises all 12 hardnesses between 2H and 9B.