KUM Artists Sharpeners are without peer with regard to materials and manufacture. KUM sharpeners are equipped with blades manufactured with ultra-hard (65 hrc) and razor-sharp high carbon steel. The blades on a KUM sharpener are harder than ball bearings or any high-quality knife, providing you with the ideal instrument to sharpen the hard, quality graphite found in Artists pencils. Two step long cone sharpener. The first blade removes wood from the lead until it reaches the automatic stop. The 2nd blade sharpens the lead to an extra long point. The automatic stop prevents further sharpening.