5pcs 6.5mm Nitride Titanium Coated High Speed Steel (HSS) 4341 Twist Drill Bits 9mmx9mm Product Name: Door Viewer

Product Name: Door Viewer

Work well on kinds of texture material

First round the iron pipe with white paper

Installed in the square hole machine directly

5pcs 6.5mm Nitride Titanium Coated High Speed Steel (HSS) 4341 Twist Drill Bits 9mmx9mm Product Name: Door Viewer4341 high speed steel contains high content of carbon and alloy elements, providing excellent cutting performance, high heat resistance, high hardness, wear resistance and durability. Suitable for applications requiring precise and efficient processing. Black nitride and gold titanium dual coatings can apply lubricant better for smoother drilling and are more durable and corrosion resistant. Large spiral grooves facilitate the export of metal chips,