Klann Tool's universal tool for stud extraction and insertion is impact-rated and offered in either 3/8" or 1/2" drives. Simply attach the extractor and turn down the impact gun's torque setting as low as it will go or reduce its air pressure. The slow, steady chattering or vibration that results will first break the corrosion bonding the stud and then unscrew it. The tool's stepless adjustment design accommodates any stud diameter from 6mm. to 12mm (1/4" to1/2").