Abstract: A screening device having a screen deck composed of two screen frames (11, 27) provided with oblong, parallel screening elements (20, 28), the elements (20) of the first frame being arranged between the elements (28) of the second frame. The second frame (27) rests on the first frame (11). The frames are provided with guide and contact elements (22-26, 32) for guiding and retaining the second frame in a predetermined position on the first frame. The second frame (27) can, in order to free material particles which have jammed between the screening elements (20, 28), be raised freely relative to the first screen frame to a predetermined maximum height, the frames and their screening elements remaining parallel to one another. The frames can be resiliently supported for performing oscillating movements relative to a support frame (5) and relative to one another.