6-60mm Hss Step Drill Bit Spiral Conical Slot Countersink precise cutting technology is adopted

precise cutting technology is adopted

the internal top bumper can absorb all kinds of accidental impact energy

you can not only enhance the strength of the fingers

which is made of wood

and flour types can effect the rise

6-60mm Hss Step Drill Bit Spiral Conical Slot Countersink precise cutting technology is adopted6 60mm Hss Step Drill Bit Spiral Conical Slot Countersink steps: 6,10,15,20,25,30,35,40,45,50,55,60mm). Shank diameter: 13 mm. Step drill Material: HSS 4241Application: The step suitable for workpieces with hardness below 25, such as carbon steel, sheet metal, insulation board, PVC board, board and wood. The thickness of the part under 5mm. Note: Use water cooling in the drill to extend the life of the bit. Recommended drilling speed 250 400 rpm.