The invention relates to a valve (1) comprising a valve casing (2), a cone (4) with a shaft (40) emanating from the cone (4), and a seat (20). The valve has a control element (3) for moving the cone (4) to and from the seat (20). The control element (3) comprises a first leg (30) located outside the valve casing (2) and a second leg (31) which is at least partially located inside the valve casing (2). The second leg (31) passes through and is firmly attached to an elastic and springing-back wall section (21) on the valve casing (2) which faces the seat (20) and its lower end (310) merges into the shaft (40) via a joint (5). When the valve is closed the springing-back wall section (21) presses the cone (4) against the seat (20) via the second leg (31) and the shaft (40).