... a portable rock drill tool,composed of a small petrol engine,ann air compressor and a rock drill.During oiperation,rock ... .It is a Kind hand held drill built up with gasoline engine,Air pump,rock drill and the rotation plumbum equipment for ... *H)746*315*229 mmDiameter of engine pistonφ58 mmStroke of engine piston70 mmRotating speed of engine with load>=2450 rpmDrilling speed>=250 ...