The BMG-435P Gas Powered Grinder Small Wet Dry Grinder Polisher is an ideal machine for preparing surfaces prior to new coatings. Perfect for removing old coatings or adhesive residues, to smooth or flatten concrete slabs including curled expansion joints, or to just simply remove unsightly surface imperfections. For decorative concrete applications, it may be used with the new Chryso Brush System to do dry finish exposed aggregate concrete. Using a surface retarder like traditional exposed, the Chryso Brushes are used to remove the surface grout and expose the aggregate beneath the surface.