If you need a round hole, reach out to the expert sawing and drilling contractors at Concrete Cutting Systems Inc for a diamond core drill! We can drill any size hole from 1/4" to 36" in diameter. Core drill units are comprised of a diamond core bit, drill motor, drill post, and an electric or hydraulic power source. The most common uses for core drills include plumbing, electrical, test cores, bumper posts, handrail, anchor bolts, and thick concrete demolition.