Abstract: To reliably expose the treated organ during surgical procedures, retraction devices are used with a holding arm (2) to which clamps (1) or the like are fastened, so that the clamps (1) canquickly be replaced and brought into a new position at the holding arm (2), the holding arm (2) designed as a rod with a hollow space, in which a blade-shaped locking bar (13) is guided. The holding arm (2) has openings (3), and the locking bar (13) has notches (12) aligned with the openings (3), so that, in the unlocked position, the openings (3) are exposed, while, in the locked position they are partly covered by the locking bar (13). Clamps (1) with shafts (10) can be inserted into the openings (3). The shaft (10) of a clamp (1) has a groove (11), into which the locking bar (13) can be slid, so as to fasten the clamp (1) in the opening (1) of the holding arm (2).