F1 Boring Head 12/18/25mm Boring Bar Milling Holder for Milling Machine Tools In $103.5 Hole Diameter F1-12-50 (2 Inch) Hign-concerned Chemical None Brand Unbranded Material 20CrMnTi Range 10-320mm Hardness HRC58 Certification CE Model Number F1 Boring condition New Material: 20CrMnTi Hardness:HRC58 Accuracy: 0.01mm Range: 10-320mm