Replaceable head drill body HYDRA with DIN 6535HE NC whistle notch shank, size 21.0mm with an overall length of 266.5mm and flute length of 184.5mm according to DORMER standard for 8xD drilling with HYDRA P (R950), HYDRA M (R960) or HYDRA K (R970) diameter 20.64 up to 21.5mm
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