Premium Dry Core Drills. For drilling fast,clean and accurate holes through soft brick,concrete block and other abrasive materials. *Fits standard electric drilling machines over 850 watt. *Up to three times the drilling speed of carbide core bits. *Clean,accurate holes with no material back breakout. *Lower noise than conventional methods. *Back end fitting 1/2" BSP *Barrel length 150mm *Drill adaptors available SDS Plus,SDS Max and Hex fitting.