Bosch Expert Hex-9 Hard Ceramic Multimaterial Drill Bit for Impact Drill Driver 3mm 4mm 5mm 6mm 8mm 10mm 12mm Bosch AccessoriesHEX 9 Hard Ceramic Drill Bit offers an extremely long lifetime when drilling in even the hardest grade of tiles and glass Carbide head with multiple sharp cutting edges that reduce wear and ensure smooth drilling Centring tip for easy drilling starts without slipping Hex shank for a strong connection and maximum torque transmission in three jaw chucks and " internal hex tool holders Extreme Endurance for Tough Materials HEX 9 Hard Ceramic Drill Bit