Carter Diamond Tool Corp.'s (Willoughby, Ohio, U.S.A.) synthetic diamond drills are designed for high-volume hole drilling operations in aircraft and other aerospace applications that involve non-metallic materials, including carbon fiber- and glass fiber-reinforced plastics, pre-fired ceramics and nonferrous metals, such as aluminum and magnesium. Drills are available in standard sizes, ranging from 1/8th to 7/16th inch in diameter. Dull drills may be resharpened to slightly smaller size for reuse. .