F Lead Grade
The F lead grade falls in the 11th position of 22 on the widely recognized 10H-10B scale (H=hard, B=black). F is considered 1 of the 3 central positions, dark enough to read whilst hard enough to minimise smudging
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The F lead grade falls in the 11th position of 22 on the widely recognized 10H-10B scale (H=hard, B=black). F is considered 1 of the 3 central positions, dark enough to read whilst hard enough to minimise smudging
