These carbon pencil leads are great for all of your writing needs. Designed for use with Staedtler Mars Technico lead holders, this high-quality carbon lead is ideal for using for drafting, designing, sketching, paper crafting and more. Details: HB degree2 mm5.125" (13 cm) long12 packs (6 leads per pack, 72 total leads)For use with standard 2mm lead holders