Shank: 1/2"(12.7mm) 12mm 8mm 1/4"(6.35mm) 6mm. 1PC 3Flutes Countersink Drill Bits 20.5/25/30mm 90 Degree HSS Chamfering Cutter. 6mm-100mm Diamond Hole Saw Cutter Drill Bit Set for Tile Glass Ceramic Marble.
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