These leads are formulated under an exclusive process to improve strength yet retain blackness and smoothness. Excellent for technical drawings, fine art, writing and more; create dark, clean lines with just a touch of pressure. Details:BlackAvailable in multiple grade sizesFits 0.3 mm mechanical pencils12 pieces of leadProduces extra fine linesStrong and durableReduces the risk of lead breakage Packaged in protective plastic tubesPolymer lead