The Ideal 35-521 is a Quick Change Step Drill Bit. This new aggressive split-point tip lasts longer and starts faster than competitors bits. Made of a high speed tool steel it is the most durable steel available for cutting tools, giving any tool that it's used in a longer life span. The tip of this bit is double-tempered for a superior life span, the double-fluted and blended radius steps for smooth and accurate drilling. A 1/4" quick-change shank can be used in standard 3-jaw chunk, impact drivers and quick-change drill chucks. In 1916, J. Walter Becker started the Ideal Commutator Dresser Company of Chicago from his mother's kitchen. Service, he said, was part of the product. That idea has been the core IDEAL business principle for over 90 years. Today, the many loyal distributors and customers that make IDEAL successful are a testament to Becker's original philosophy.