4 - 22mm Hex Titanium Step Cone Drill Bit Hole Cutter HSS 4241 for Deburring ChamferingMain Features:● A bit can open a variety of specifications of aperture.● Do not need to use center punch, compared with the ordinary twist drill, it is not easy to be broken.● Deburring, chamfering, elliptic hole enlargement.● Use for drill, bench drill. Work w...