HEXAGONAL --- The Shanks Are Hexagonal That Can Be Gripped Tightly, So It Won’t Slip out Easily. Can Be Used with Hand Drill, Bench Drill. Drill Bits 3 PCS Diamond Hole Saw Set 6mm 8mm 10mm Hexagonal Dry Drill Bits with Wax Insert for Glass Ceramic Tile Porcelain Marble Granite.
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