The Bosch GDS 18V-LI HT 18V Cordless Impact Wrench is a powerful yet lightweight machine which produces high torque for tough screwdriving applications in metal. It is extremely robust due to an all-metal gearbox and metal housing. Specification: Bit Holder: 1/2in External Square No Load Speed: 0-1,900/min. Impacts Per Min.: 0-2,100/min. Max. Torque: 650Nm Capacity: M12-M20 Weight: 3.0kg