Hardness mark of pencil lead

The hardness mark of the pencil lead, generally use "H" for hard pencil, "B" for soft pencil, "HB" for soft and hard lead dao pen, "F" for pencil with hardness between HB and H .

Arrangement (from soft to hard) 9B, 8B, 7B, 6B, 5B, 4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, 9H, 10H, etc. Hardness level.

The larger the number in front of H, the harder the lead and the lighter the color.

The larger the number in front of B, the softer the lead and the darker the color. The classification of pencil rods is based on the amount of graphite in the refill. Among them, Type H pencils have relatively high refill hardness and are suitable for objects with relatively hard or clear interfaces, such as carpentry marking, field drawing, etc.; Type HB pencil refills have moderate hardness, suitable for writing under normal circumstances, or playing For contours; Type B pencils, the refill is relatively soft, suitable for painting, and can also be used to fill some machine-recognizable cards. For example, we often use 2B pencils to fill in the answer sheet. In addition, there are also colored pencil rods, which are often referred to as colored pencils, and are mainly used for drawing.