Extra heavy duty 15.0 AMP motor for high production; lock-on feature for continuous operation 6,000 RPM for fast material removal Rugged metal housing for longer tool life All-ball and needle bearing construction for longer tool life Accepts 7" or 9" wheel with correct guards Side handle can be installed on either side of the tool AC/DC switch for use with alternative power source Spindle lock for easy wheel changes Standard 5/8" x 11 UNC spindle thread for various accessories