This is a 66 tooth 4 inch diameter high carbon steel circular saw blade, made in the USA. The blade has a rim thickness of approximately 0.045 inch (1.14 mm), plate thickness of 0.032 inch (0.81 mm) and a 1/2 inch arbor (hole). This blade can also be used in applications that require a 4 inch blade with 3/8 inch arbor. A 1/2 inch to 3/8 inch bushing for this will be included at no additional charge, if requested with your payment. This blade is designed to cut soft and hard wood, but not metal. It is a close replacement for the original Dremel combination blade No. 8003. Please follow all safety instructions that come with the blade and the safety instructions that were provided by the saw manufacturer.