Abstract: A lever-arch type file mechanism (100, 200, 300) is disclosed as including a base (102) two rings secured to and extending upwardly from the base (102) for engaging holes in pieces of paper, each ring including a post (104, 204) fixed to the base (102) and an arch element (106, 206) movable relative to the base (102) and the post (104, 204); a lever (110, 210, 310) operable to move the arch elements (106, 206) relative to the posts (104, 204) between a closed configuration in which the rings are closed and an open configuration in which the rings are open; and the arch elements (106, 206) are joined by an integrally formed bent section (120, 220) which is asymmetrically bent about its mid point.