An occluding device for closing a body passage comprises an occluding body (1), a first position control element (2) and a second position control element (3). The occluding body (1) is a balloon made of a flexible and fluid tight material without shape memory property. The occluding body (1) comprises a proximal chamber (10) and a distal chamber (11) and a connecting channel (12) connecting these two chambers (10, 11). The occluding body (1) is compressible into a first longitudinal shape. A proximal end of the occluding body (1) is attached to the first position control element (2) and the distal end of the balloon is attached to the second position control element (3). The first position control element (2) and the second position control element (3) are two matching parts of a fluid tight closure of the balloon. The occluding body (1) is adapted to be brought into a second inflated shape by introduction of a fluid and into a third radially extended but longitudinally compressed shape by evacuating this fluid and by bringing the two position control elements (2, 3) into a snapped together position. No additional stiffening means for stiffening the balloon in its third radially extended but longitudinally compressed state are arranged within the occluding body (1). This occluder allows rearrangement of the balloon within the defect and it enables to adapt the shape of the balloon to the patients anatomy.
