3 Countersink Drill Bit. 1/4" Quick Change Hex Shank. Shank:(Optional) Hex, 1/4 Round. Material: Carbon Steel. Set Features all Commonly used Sizes Including 12mm, 16mm& 19mm all with 1/4" Hex and Round Quick Change Shanks to Facilitate Fast Changing with a 1/4" Quick Chuck.
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