Drilling is the most widely used method of concrete penetration by contractors. Sanders Saws stocks a variety of core bits to drill holes as small as 1/2" to 18" in diameter. Special bits for holes bigger in diameter and deeper in depth are available. These bits are typically used on larger hi-cycle or hydraulic drilling equipment. Depending on the psi of the concrete, aggregate type, and amount of steel, there are various types of bond hardness and grade specifications to choose from.