Makita delivers corded grinding performance without the cord with the 18V LXT Lithium-Ion Brushless 4-1/2” Cut-Off/Angle Grinder with Electric Brake (XAG09Z, tool only, batteries 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. For added convenience, the XAG09Z has an electric brake that stops the wheel in 2 seconds or less upon release of the switch. The XAG10Z is ideal for grinding, cutting and sanding a wide range of materials including tile, concrete, pipe, conduit, and more. 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.