Makita delivers corded grinding performance without the cord with the 18V LXT Lithium-Ion Brushless 4-1/2"/ 5? Paddle switch Cut-Off/angle Grinder with Electric brake (tool only, battery and charger sold separately). it's powered by a Makita Brushless motor for longer run time, increased power and speed, and longer tool life. For the most demanding applications, Makita?s exclusive automatic speed Change? technology automatically adjusts speed and torque during operation for optimal performance. The XAG20Z is ideal for grinding and cutting a wide range of materials including tile, concrete, pipe, conduit, and more. Additional features include an Electric brake that stops the grinding or Cut-Off wheel in 2 seconds or less, and electronic torque control that turns the motor off if rotation speed suddenly slows or the wheel is forced to a stop. The variable speed control dial allows manual RPM adjustment (3, 000 ? 8, 500), allowing the user to match the speed to the application. It?S part of Makita?s expanding 18V Lithium-Ion system, the world?s largest cordless tool system powered by 18V Lithium-Ion slide-style batteries. Makita 18V Lithium-Ion batteries have the fastest charge times in their categories, so they spend more time working and less time sitting on the charger. For improved tool performance and extended battery life, Makita created Star protection Computer controls?. Star protection is communication technology that allows the Star Protection-equipped tool and battery to exchange data in real time and monitor conditions during use to protect against overloading, over-discharging and overheating. For increased versatility, the tool can also be powered by Makita 18V LXT and compact Lithium-Ion batteries with the Star symbol on the battery indicating Star protection inside. Electric brake stops the grinding or cut-off wheel in 2 seconds or less for maximum productivity Active feedback-sensing technology (aft) turns the motor off if rotation of the wheel is suddenly forced to stop Automatic speed change technology adjusts speed and torque during operation for optimum performance The BL Brushless motor eliminates carbon brushes, enabling the BL motor to run cooler and more efficiently for longer life Variable speed control dial allows Manual RPM adjustment (3, 000-8, 500) to match the speed to the application