The TW004GZ01 a compact & lightweight Brushless Impact Wrench, powered by 40V Max XGT battery, to supply power to the powerful 40V Max brushless motor, with variable speed controlled by trigger & constant speed control to automatically apply additional power to the motor to maintain constant speed under load, to deliver up to 4, 000 ipm, 3, 200 rpm, 350 Nm maximum fastening torque & 630 Nm nut busting torque for high performance in continuous heavy duty applications. The TW004GZ01 is equipped with electric brake to stop the rotation gently but quickly for increased operator safety, forward & reverse rotation, electronic 4 stage impact power selection for maximum, hard, medium & soft & LED job light to illuminate the work area. The TW004GZ01 features trigger switch with full speed mode; variable speed mode can be changed to full speed mode simply by pushing a button. In full speed mode, the trigger travel is shorter, reaching full speed quicker, 3 modes of reaction time for automatic stop, available in both the forward & reverse rotation modes & reverse rotation auto stop mode; stops after the bolt/nut has loosened enough. The TW004GZ01 is equipped with 12;” square drive (c-ring) & has a M10 to M20 capacity standard bolt & M10 to M16 capacity high strength bolt.