Overview Reviews Product Description Cobalt jobber drills offer increased hardness, toughness and better wear resistance compared to regular HSS Gold oxide surface finish provides a polished finish and prevents chip building, galling and welding on a workpiece 135° Degree split point (self-centering) which eliminates "walking" and reduces the thrust force Cobalt drills are suitable for harder material including alloy steels, stainless steel and other difficult to drill materials Clarkson Osborn Catalog Product Videos Custom Field Diameter 8.4mm Flute length 75mm Overall length 117mm Package quantity/sold as each 10 Product Reviews Write a Review Write a Review × Clarkson-Osborn 8.4mm Cobalt Jobber Drill Bit DR90840 Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Review Subject * Comments *