Motor Type: Brushless motor for higher efficiency, less heat, and zero carbon brush maintenance.Voltage: 20V MAX.Speed: Variable speed control ranging from 3,000 to 9,000 RPM.Disc Diameter: Standard 4.5-inch (115mm) or 4-inch (100mm) options.Spindle Thread: M14 or 5/8"-11UNC depending on regional model.Kit Contents: Often sold as a complete kit including a 3.0Ah or 4.0Ah battery, a fast charger, a side auxiliary handle, and a metal safety guard.