... changes, heavy automotive and truck work. DESCRIPTION:XF-231 Air Impact Wrench*square drive size:1/2"*capacity bolt dia.:16mm*free ... with no load:149L/minSPECIFICATION :1/2" air impact wrench set*1/2" air impact wrench*1pc extention bar*1pc mini oiler*1pc air ... ,15,17,19,22,24,27mm Twin Hammer Type Air Impact Wrench