Replaceable head drill body HYDRA with DIN 6535HE NC whistle notch shank, size 21.0mm with an overall length of 156.5mm and flute length of 76.5mm according to DORMER standard for 3xD drilling with HYDRA P (R950), HYDRA M (R960) or HYDRA K (R970) diameter 20.64 up to 21.5mm
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