Thick wall construction core drills with large brazed tungsten carbide teeth will easily drill medium/large diameter holes even in the hardest concrete. A female 'K' taper mount enables the core drills to be used on the flexible 'K' taper drilling system, using various adaptors and extensions. For use with most electric rotary hammers, including SDS Plus and SDS Max, using Toolpak 'K' taper drill holders. Suitable for drilling clean holes in concrete, brick and aerated block.