Replaceable head drill body HYDRA with DIN 6535HE NC whistle notch shank, size 11/16" with an overall length of 136.5mm and flute length of 62.5mm according to DORMER standard for 3xD drilling with HYDRA P (R950), HYDRA M (R960) or HYDRA K (R970) diameter 0.6535 up to 0.689"
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