Silverline - DIAMOND CORE DRILL HEX 78X150MM - 762171 High performance dry cutting, diamond core drills. Cut clean accurate holes through bricks & blocks, producing exact size holes with almost no break out. Core can be removed in one piece avoiding the need for making good by a brick layer or plasterer. Suitable for concrete, brick, paving slabs, asphalt, limestone, clay bricks & aerated block. For use with Silverline arbor & guide drill.