BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to peristaltic rings equipped with multi-stage locking by double rotation. More specifically, it is possible to use a variety of fastening lines irrespective of the size of the fastening line by providing an extended space in the upper part of the inside of the fastening ring in the fishing operation using the fastening net, And particularly, the tight locking between the annular lock portion and the hook-shaped lock retaining portion maintains the locked state, so that the load generated by the interaction between the persisting ring and the tightening rope when deploying and recovering the pick- The present invention is not limited to the above-described embodiments, and it is an object of the present invention to provide a multi-stage locking device capable of preventing detachment of the fastening string moving in the inside of the fastening ring and breakage of the fastening ring, Ring. To this end, the present invention provides an image forming apparatus comprising: a roller portion including a roller that rotates when a saw chain is in a rolling contact with a reciprocating motion； A hinge engaging portion formed at an upper end of the incision portion and hinged to open and close the incision portion, a hinge engaging portion formed at a lower end of the incision portion, the incision portion being formed at a lower end of the incision portion, A body portion including a ring-shaped locking portion for locking the card when the card is closed, and a roller insertion portion into which the roller can be inserted； And a locking guide groove extending from a lower side of the latching head to guide the locking / unlocking and rotating movement of the latching head, and a hook-shaped A spring that is inserted into the outer circumferential surface of the latch body portion, a spring that is inserted into the outer circumferential surface of the latch body, a lower side of
