The BL Brushless motor eliminates carbon brushes, enabling the BL Motor to run cooler and more efficiently for longer life; delivers 6, 000 RPM Two 18V LXT Lithium-Ion batteries deliver corded power without leaving the 18V LXT battery platform (batteries not included) Active feedback-sensing technology (aft) turns the motor off if rotation of the wheel is suddenly forced to stop Electric brake stops the grinding or cut-off Wheel in 4.5 seconds or less for maximum productivity Auto-start Wireless system (AWS) utilizes Bluetooth technology for wireless Power-on/off communication between tool and dust Extractor