Functionsthe "FOR ALL" 2B graphite lead enables you to make markings on the surface of almost any material. No matter whether it is dry or wet, smooth or rough, dusty or oilycan be wiped from smooth surfaces with a damp clothfor light or dark surfacesintegrated sharpener in the quiver cappressure mechanism for automatic lead feed in the stainless steel tubelead diameter: 2.8 mm