Bosch DDB3PC Porcelain Diamond Drill Bit Set, 3 Pack:

• Diamond Drill Bit Easy Dry makes dry drilling in ceramic easy
• Dry-drilling bit design – engineered for accurate dry drilling in porcelain and natural stone tile, for a precise, clean hole
• Built-in wax insert in tip – lubricates and cools the hole without the need of water
• Drilling control – dry drilling allows for drilling with two hands, providing more control when drilling, for more precision
• Vacuum-brazing technology – fuses high-quality diamonds to the bit tip for 10x longer bit life in porcelain than standard glass and tile bits