The Numbers Softer cable gets a B rating, with a number that indicates how soft the lead is. B alone is slightly softer than HB. Higher in the range, the 9B is the softest cable available, yet so soft and brittle that it's rarely used. Tips for mechanical pencils and hand pencils are available in a variety of diameters and standard hardness grades.
In the past, pencil manufacturers used combinations of letters to give us more information about graphite; a pencil marked with HB is hard and black, a pencil marked with HH is very hard and a pencil marked with BB is very black. This simple grading system has been expanded in recent decades to include many more degrees. Most modern pencils that use the HB scale have a designation with letters accompanied by a number (such as 2B, 6B or 5H) to indicate the degree of hardness or blackness. Combining any grade H lead cable, especially with toothed paper, will give you a better writing or drawing experience, as graphite adheres more effectively to the textured surface and is seen more clearly.
Grade 2B doesn't fully exceed the natural limitations of soft lead and is still a bit fuzzy. Choosing the right pen for writing or drawing is just as important as selecting a lead grade. Writers can fine-tune the darkness of their lines by increasing or decreasing the hardness of lead, while an artist can use the full range of lead grades to achieve different effects. Whether it's wooden pencils, mechanical pencils, or lead holders, lead quality is an important consideration for writers and artists alike.
Every pencil, whether a mechanical pencil or a wooden pencil, has a tip and each lead has a grade. But what grade of lead should you use? What is the best option for a test? What is best for art? How about taking notes? Much of choosing a pen's lead grade will depend on individual preferences, but here's a guide that can help by providing you with a starting point. Today, most pencils that use an HB system and lead ratings are designated with a combination of numbers and letters.