Freud"s precision ground carbide bits have a grain size smaller than other grades, and titanium is added making them impervious to chemical attack. Promoting safer woodworking is the reason Freud made a commitment to develop anti-kickback router bits. Bits are computer balanced to insure vibration-free operation at speeds that are a safe margin above the typical 22,000 RPMs of most routers. Freud"s philosophy is woodworkers should expect safety, not pay for it. Over all diameter 1-1/2-inch, radius 1/2-inch, shank diameter 1/4-inch.