
Drawing pencil is an important tool which is used in engineering drawing and sketching. These drawing pencils are made up of graphite, wooden casing, clay, brass, aluminium for ferrules and other material. Numerous types of pencils are used in drawing such as H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, 9H, B, HB, 2B, 3B, 4B, 5B AND 6B. Pencil manufactures using the letter "H" in order to indicate a hard pencil. Although, most pencils manufacture using the HB system are designated by a number, namely 2B, 4B or 2H in order to specify the degree of hardness.