High performance, dry cutting diamond core drill bit. Cuts 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 bricklayer or plasterer. Suitable for concrete, brick, paving slabs, asphalt, limestone, clay bricks & aerated block. For use with Silverline arbour & guide drill. Not suitable for sinking sockets. Produces exact size holes with almost no break out. Core can be removed in one piece. Suitable for dry cutting concrete, brick, paving slabs, asphalt, limestone, clay bricks & aerated block. For use with Silverline arbour & guide drill. Not suitable for sinking sockets.