Dewalt dcf899m1 20v max xr brushless torque 1/2 impact wrench detent pin anvil (included) size 1/2 power source battery-powered voltage 20 volts torque 700 in-lb the dewalt dcf899m1 20v max xr brushless high torque 1/2 impact wrench with dentent pin anvil (4.0 ah) features up to 700 ft-lbs of max torque and 1200 ft-lbs of max breakaway torque.