Pentel Premium Hi-Polymer Lead refill has leads to offer smooth uniform writing & produce smooth / dark lines with reduce smearing. Each lead strand will last as long as a #2 wood pencil. For use with most refillable automatic pencils & Pentel mechanical pencils. Pencil Lead Format: Tube; Lead Diameter: 0.5 mm; Lead Degree (Hardness): 2B; Lead Color: Black.