An electric power tool for tightening screw joints includes a housing that encloses an electric motor, an angle gear, a back torque transducer, and a front torque transducer. The angle gear includes an input bevel gear drivingly connected to the electric motor and an output bevel gear drivingly connected to an output shaft of the electric power tool. The back torque transducer is arranged to measure a back torque reaction value before the input bevel gear. And the front torque transducer is arranged to measure a front torque reaction value after the output bevel gear.