1/ 2" Heavy Duty Air Impact Wrench Twin hammer mechanism Front exhaust Super power for car tire maintenance & assembly line 1/ 2" Heavy Duty Air Impact Wrench( Twin Hammer) 1. Square drive: 1/ 2" 2. Air pressure: 90psi 3. No-load speed: 7500rpm 4. Capacity bolt dia.: M16( mm) 5. Max Torque: 550n. M 6. Vibration of square head: