Shank: 1/4"(6.35mm) 6mm. Shank Material: High Speed Steel. 6mm-100mm Diamond Hole Saw Cutter Drill Bit Set for Tile Glass Ceramic Marble. Radius: 1/8 1/4 5/16 3/8 7/16 1/2. High Speed Steel Body. Cutting sharp, smooth rotation, brisk operation.
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