Patent attributes
A rotary wrench including a working head and a handle. The handle has two arms defining a holding space in which the working head is installed. The two arms are respectively formed with a first thread hole and a second thread hole with different spiral directions and opposite to each other. The working head has a first threaded end and a second threaded end opposite to each other respectively corresponding to the first and second thread holes of the handle. The first and second threaded ends have different spiral directions respectively corresponding to the spiral directions of the first and second thread holes of the handle. The first and second threaded ends of the working head are respectively screwed in the first and second thread holes of the handle. When the working head is screwed toward one side of the handle, the two arms are contracted to clamp the working head, while when the working head is screwed toward the other side of the handle, the two arms are stretched to loosen the working head and permit the working head to adjustably rotate relative to the handle into a predetermined angular position.