The Irwin IRW10507900 Diamond Drill Bit 4 Piece set comprises one of each of the following diameters: - 5 mm - 6 mm - 7 mm - 8mm - The Irwin Diamond tipped drill bits are suitable for fast smooth cutting in all grades of hard and soft tiles. - Their raised diamond grit edge makes for easy starting in hard tile without the need for a guide. - The diamond grit is tough brazed diamond which ensures fast cutting and long life. - The drill bit's reverse spiral forces water towards its cutting head, keeping the diamonds cool to increase cutting speed and prolong life. - Drilling with water will further increase the lifespan of the tool. - The auto slug ejection slot allows the bits to be used for continuous, uninterrupted cutting.
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