The Milwaukee 2780-20 4-1/2" 18V Cordless Grinder is the first tool of its kind that delivers the convenience of cordless capabilities without sacrificing the speed and power you expect from a corded tool. Milwaukee Tools rates this tool with two times the run time, and ten times the motor life of other cordless tools. New Technological features like the POWERSTATE Brushless Motor, and the M18 REDLITHIUM XC4 Battery Pack (Sold Separately) are the main driving forces that are used to accomplish these superior results. Another feature that Milwaukee included is the design of this Milwaukee 2780-20 4-1/2" Grinder is REDLINK PLUS Intelligence. This state of the art technology provides optimal performance by utilizing an electronic clutch, and total system communication between battery, tool, and charger providing optimal overload protection while minimizing equipment overheating. This 18 volt Lithium Ion grinder is built with the same slim body design, gearing system and anti-vibration side handle as the corded version insuring maximum durability and optimized balance and control. Along with a full 5 year warranty the Milwaukee 2780-20 4-1/2" 18V Cordless Grinder incorporates a Tool-free Design for quick and efficient accessory changes and guard adjustments resulting in less downtime at work.