Bosch 1773AK 5-Inch Concrete Surfacing Grinder 10-amp concrete surfacing grinder, perfect for smoothing floor pavement, removing graffiti, cleaning concrete surfaces Also ideal for removing irregularities, formwork seams and protrusions Double sealed ball bearings and two -Inchlip-sealing-Inch protective rings for added protection against dust contamination 5-Inch wheel diameter, 11,000 RPM Wrap-around auxiliary handle for easy handling