HB Lead Grade
The HB lead grade falls in the 12th position of 22 on the widely recognized 10H-10B scale (H=hard, B=black). HB is considered 1 of the 3 central positions, dark enough to read whilst hard enough to minimise smudging
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The HB lead grade falls in the 12th position of 22 on the widely recognized 10H-10B scale (H=hard, B=black). HB is considered 1 of the 3 central positions, dark enough to read whilst hard enough to minimise smudging
