... chiseling in speed 3.wide drilling 4.cutting scope 5.saving time and strength A, Coal rock drill is introduced,Product ... into dry and wetCoal rock drill32 Coal rock drill43 Coal rock drill45 Coal rock drill47 Coal rock drill60 B,Coal rock drill illustration,C,Coal ... alloy, it is mainly characterized by large torque, wide drilling range,easy connection and durable.D,Ruilong Consciousness,Quality is ...