Staedtler's Mars Lumograph pure graphite Pencils features a special lead formulation for creating metallic lustre results in a wide variety of grey tones. They are particularly suitable for writing, drawing, sketching and hatching, as well as for professional graphic and artistic applications.Features: contains six degrees: HB, 2B, 4B, 6B, 8B, 10B lead diameter: approx. 6.8 mm no wood-case lines reproduce well sharpener recommendation: Staedtler Mars double-hole sharpener 510 25 or sandpaper 923 for ideal sharpening results