Milwaukee® 50 Series Motor Housing is designed for 9" sander, 5" and 3" straight grinders, 125 mm straight grinders, 50 mm die grinders, 7" heavy-duty variable speed polishers, 2" die grinders, 2.25 max HP 5000 RPM 7" and 9" sanders, D. I. 6000 RPM lightweight sander, D. I. 6000 RPM dial speed grinder and 1750 RPM 7" heavy-duty polishers.