Overview Reviews Product Description Cobalt Bright and black finish Straight shank Right hand cut Left hand helix Left hand spiral flute design pushes chips forward out of the hole and allows the reamer to be used in holes that have an interruption These reamers can be run approximately 25% faster than regular HSS reamers with increased tool life due to cobalt substrate Clarkson Osborn Catalog Product Videos Custom Field Diameter 4mm Flute length 19mm Overall length 75mm Package quantity/sold as each 1 Product Reviews Write a Review Write a Review × Clarkson-Osborn 4mm Cobalt Chucking Reamer RE24540 Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Review Subject * Comments *