The combination of high carbon steel with a titanium nitride coating will keep you drilling long after other bits have become worthless. Forstner design makes smooth flat bottomed holes, or angled holes with oval openings. Stored in their own box. Shank: 3/8'' Sizes: 1/4'', 3/8'', 1/2'', 5/8'', 3/4'', 7/8'', and 1''.