ER8 ER11 ER16 ER20 ER25 ER32 ER40. ER8 ER11 ER16 ER20 ER25 ER32 ER40 Nut. Model: ER8/ER11/ER16/ER20/ER25/ER32/ER40. Non-standard ER collet chuck (ER8/ER11/ER16/ER20/ER25/ER32/ER40) Enlarge the inner hole and increase the clamping.
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