The invention relates to a detachable spring nut for fixing to a threaded bolt. The spring nut comprises two spring tabs (5), which face the centre and have curved supporting edges (6), and a spring pin (7) pressed out in an arc beneath an intermediary plate (3). As a result, the spring nut needs simply to be pressed upon for it to rest fully, as required, on the plate (13) that is to be fixed; no extra twisting is necessary. In order to undo the spring nut, several key pins (8, 9) are bent up at right angles from the edge of the bearing plate. The invention has the advantage of reducing assembly time. Furthermore, the nut is stackable, and therefore can be kept in a magazine.