Electric Concrete Floor Grinder 7" Walk-Behind Grinder 2.0HP Concrete Floor Polisher, 1500W Grinding Machine, 1400RPM Upgrade Brushless Motor Surfacing Grinder for Granite/Marble/StonesProduct Features Brushless Pure Copper Motor Prepare to witness powerful performance. The 2. 0HP pure copper motor drives the polishing machine at a speed of up to 1400 RPM, delivering strong polishing power and results. Additionally, the grinding disc is sharp, hard, and wear resistant. Replaceable Blades The concrete grinder is equipped with replaceable grinding disc blades, the diamond blades efficiently grind 3230~5382 sq. ft, compatible with