Proxxon 28782 Ball Corundum Grinding Bits 9mm Pack of 3 Pcs NO 28 782 Key Features Bits and sets of fine, high quality materials of consistent hardness. Various shapes for the widest possible range of applications. For grinding and chiselling hard materials such as cast iron, cast steel, malleable cast iron as well as hard metal alloys and refined steel. Accurately dimensioned shafts of Ø 2.35 or 3mm ensure maximum concentricity. Grinding rule: Soft materials = hard grinding bits; hard materials = soft grinding bits!.
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