The DW4899 will include (6) 6" DW4802 , (5) 6" DW4811, (2) 8" DW4809 , (2) 9" DW4803 and (1) 9" DW4805 blades.
These are cutting wheels for a 4 1/2 inch angle grinder. For a circular saw there are masonry reinforced blades that can be used to cut steel. The type of blade that you use for a circular saw depends upon the material in the blade that holds it together. Heat is a critical factor for any blade, and if the wrong blade is used in a tool the results can injure you. The DCS571B is a 4 1/2 inch circular saw that looks like it is built for cutting wood and plastics but check your manual or DeWalt.com for any specific information to help you make your final decision. Circular saws burn up quickly when they do too much masonry or steel cutting. Angle grinders are intended for light steel and masonry cutting. Constant steel and masonry cutting by a tool requires that the tool be built for that purpose because they can handle the necessary heavy work load from steel cutting or abrasive dust created by masonry cutting.
Push the thumb tab on the lid up