Staedtler Mars Carbon 2 MM Black 2B Leads (Pack Of 12) staedtler mars lumograph drawing leads - graphite leads with superior qualities for use on paper. Lay down precise, black lines that will reproduce excellently and which are smearproof and smudgeproof, yet are easily erasable. 2.0mm pencil or "lead holder" as they are commonly called uses a lead which is about the same diameter as the lead inside a wooden pencil, so it's quite large and requires sharpening if you want to write with it. It's the type of writing instrument use the most. The extra weight smooths the feedback a little compared to a wooden pencil but not enough that the the lead feels "dead" like with most mechanical pencils.