A:
The size refers to the thickness of the lead. To determine which is harder, a different scale is used. For reference lead from softest to hardest is 6B, 5B, 4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H & 9H.
Answered on 6/1/2012 by Community Answer from None