Diamond Drill BitsCutting Diameter: 5mm / 3/16", 6mm / 1/4", 8mm / 5/16", 10mm / 3/8", 12mm / 1/2"Material: Diamond, Industrial Grade Carbon Steel; Finish: Nickel PlatedPackage Content5pcs x Diamond Drill BitsDescriptions:The drill bit set with thickened electroplated diamonds have sharp cutting edge, excellent cutting strength for high precision and smooth cuts without edge breakage. Made of industrial grade carbon steel, good toughness, high strength, and durability. Nickel-plated coating provides great corrosion resistance, wear resistance, and long service life. The diamond drill bit with large clearance hole facilitates the entry of cooling water and the escape of chips from the drilled hole, making the drilling easier and faster.
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