20PCS PENCIL LEAD/PLASTIC BOX W/STICKER;1SET/BLISTERCARD24CARDS/INNER;48CARDS/CTN
Pencil Lead typesare graded by hardness and by how dark a mark they leave on the paper.
Generally, the harder the pencil, the longer it lasts, but the less lead it leaves behind. (obviously.)
Softer pencils leave heavy, dark marks. Standing right in the middle of the pencil hierarchy is the infamous #2 pencil,
known to the rest of the world as "HB". Leave it to America to develop a different scale than the rest of the world uses..
There is a large assortment of lead types available, although most of the extreme types are probably only used by artists.
The scale runs from 9B (the softest) to 9H, with a few funny named ones in the middle: